cregit-Linux how code gets into the kernel

Release 4.10 drivers/spi/spi-pl022.c

Directory: drivers/spi
/*
 * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
 *
 * Copyright (C) 2008-2012 ST-Ericsson AB
 * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
 *
 * Author: Linus Walleij <linus.walleij@stericsson.com>
 *
 * Initial version inspired by:
 *      linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
 * Initial adoption to PL022 by:
 *      Sachin Verma <sachin.verma@st.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/ioport.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/spi/spi.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/amba/bus.h>
#include <linux/amba/pl022.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/scatterlist.h>
#include <linux/pm_runtime.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
#include <linux/pinctrl/consumer.h>

/*
 * This macro is used to define some register default values.
 * reg is masked with mask, the OR:ed with an (again masked)
 * val shifted sb steps to the left.
 */

#define SSP_WRITE_BITS(reg, val, mask, sb) \
 ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))

/*
 * This macro is also used to define some default values.
 * It will just shift val by sb steps to the left and mask
 * the result with mask.
 */

#define GEN_MASK_BITS(val, mask, sb) \
 (((val)<<(sb)) & (mask))


#define DRIVE_TX		0

#define DO_NOT_DRIVE_TX		1


#define DO_NOT_QUEUE_DMA	0

#define QUEUE_DMA		1


#define RX_TRANSFER		1

#define TX_TRANSFER		2

/*
 * Macros to access SSP Registers with their offsets
 */

#define SSP_CR0(r)	(r + 0x000)

#define SSP_CR1(r)	(r + 0x004)

#define SSP_DR(r)	(r + 0x008)

#define SSP_SR(r)	(r + 0x00C)

#define SSP_CPSR(r)	(r + 0x010)

#define SSP_IMSC(r)	(r + 0x014)

#define SSP_RIS(r)	(r + 0x018)

#define SSP_MIS(r)	(r + 0x01C)

#define SSP_ICR(r)	(r + 0x020)

#define SSP_DMACR(r)	(r + 0x024)

#define SSP_CSR(r)	(r + 0x030) 
/* vendor extension */

#define SSP_ITCR(r)	(r + 0x080)

#define SSP_ITIP(r)	(r + 0x084)

#define SSP_ITOP(r)	(r + 0x088)

#define SSP_TDR(r)	(r + 0x08C)


#define SSP_PID0(r)	(r + 0xFE0)

#define SSP_PID1(r)	(r + 0xFE4)

#define SSP_PID2(r)	(r + 0xFE8)

#define SSP_PID3(r)	(r + 0xFEC)


#define SSP_CID0(r)	(r + 0xFF0)

#define SSP_CID1(r)	(r + 0xFF4)

#define SSP_CID2(r)	(r + 0xFF8)

#define SSP_CID3(r)	(r + 0xFFC)

/*
 * SSP Control Register 0  - SSP_CR0
 */

#define SSP_CR0_MASK_DSS	(0x0FUL << 0)

#define SSP_CR0_MASK_FRF	(0x3UL << 4)

#define SSP_CR0_MASK_SPO	(0x1UL << 6)

#define SSP_CR0_MASK_SPH	(0x1UL << 7)

#define SSP_CR0_MASK_SCR	(0xFFUL << 8)

/*
 * The ST version of this block moves som bits
 * in SSP_CR0 and extends it to 32 bits
 */

#define SSP_CR0_MASK_DSS_ST	(0x1FUL << 0)

#define SSP_CR0_MASK_HALFDUP_ST	(0x1UL << 5)

#define SSP_CR0_MASK_CSS_ST	(0x1FUL << 16)

#define SSP_CR0_MASK_FRF_ST	(0x3UL << 21)

/*
 * SSP Control Register 0  - SSP_CR1
 */

#define SSP_CR1_MASK_LBM	(0x1UL << 0)

#define SSP_CR1_MASK_SSE	(0x1UL << 1)

#define SSP_CR1_MASK_MS		(0x1UL << 2)

#define SSP_CR1_MASK_SOD	(0x1UL << 3)

/*
 * The ST version of this block adds some bits
 * in SSP_CR1
 */

#define SSP_CR1_MASK_RENDN_ST	(0x1UL << 4)

#define SSP_CR1_MASK_TENDN_ST	(0x1UL << 5)

#define SSP_CR1_MASK_MWAIT_ST	(0x1UL << 6)

#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)

#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
/* This one is only in the PL023 variant */

#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)

/*
 * SSP Status Register - SSP_SR
 */

#define SSP_SR_MASK_TFE		(0x1UL << 0) 
/* Transmit FIFO empty */

#define SSP_SR_MASK_TNF		(0x1UL << 1) 
/* Transmit FIFO not full */

#define SSP_SR_MASK_RNE		(0x1UL << 2) 
/* Receive FIFO not empty */

#define SSP_SR_MASK_RFF		(0x1UL << 3) 
/* Receive FIFO full */

#define SSP_SR_MASK_BSY		(0x1UL << 4) 
/* Busy Flag */

/*
 * SSP Clock Prescale Register  - SSP_CPSR
 */

#define SSP_CPSR_MASK_CPSDVSR	(0xFFUL << 0)

/*
 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
 */

#define SSP_IMSC_MASK_RORIM (0x1UL << 0) 
/* Receive Overrun Interrupt mask */

#define SSP_IMSC_MASK_RTIM  (0x1UL << 1) 
/* Receive timeout Interrupt mask */

#define SSP_IMSC_MASK_RXIM  (0x1UL << 2) 
/* Receive FIFO Interrupt mask */

#define SSP_IMSC_MASK_TXIM  (0x1UL << 3) 
/* Transmit FIFO Interrupt mask */

/*
 * SSP Raw Interrupt Status Register - SSP_RIS
 */
/* Receive Overrun Raw Interrupt status */

#define SSP_RIS_MASK_RORRIS		(0x1UL << 0)
/* Receive Timeout Raw Interrupt status */

#define SSP_RIS_MASK_RTRIS		(0x1UL << 1)
/* Receive FIFO Raw Interrupt status */

#define SSP_RIS_MASK_RXRIS		(0x1UL << 2)
/* Transmit FIFO Raw Interrupt status */

#define SSP_RIS_MASK_TXRIS		(0x1UL << 3)

/*
 * SSP Masked Interrupt Status Register - SSP_MIS
 */
/* Receive Overrun Masked Interrupt status */

#define SSP_MIS_MASK_RORMIS		(0x1UL << 0)
/* Receive Timeout Masked Interrupt status */

#define SSP_MIS_MASK_RTMIS		(0x1UL << 1)
/* Receive FIFO Masked Interrupt status */

#define SSP_MIS_MASK_RXMIS		(0x1UL << 2)
/* Transmit FIFO Masked Interrupt status */

#define SSP_MIS_MASK_TXMIS		(0x1UL << 3)

/*
 * SSP Interrupt Clear Register - SSP_ICR
 */
/* Receive Overrun Raw Clear Interrupt bit */

#define SSP_ICR_MASK_RORIC		(0x1UL << 0)
/* Receive Timeout Clear Interrupt bit */

#define SSP_ICR_MASK_RTIC		(0x1UL << 1)

/*
 * SSP DMA Control Register - SSP_DMACR
 */
/* Receive DMA Enable bit */

#define SSP_DMACR_MASK_RXDMAE		(0x1UL << 0)
/* Transmit DMA Enable bit */

#define SSP_DMACR_MASK_TXDMAE		(0x1UL << 1)

/*
 * SSP Chip Select Control Register - SSP_CSR
 * (vendor extension)
 */

#define SSP_CSR_CSVALUE_MASK		(0x1FUL << 0)

/*
 * SSP Integration Test control Register - SSP_ITCR
 */

#define SSP_ITCR_MASK_ITEN		(0x1UL << 0)

#define SSP_ITCR_MASK_TESTFIFO		(0x1UL << 1)

/*
 * SSP Integration Test Input Register - SSP_ITIP
 */

#define ITIP_MASK_SSPRXD		 (0x1UL << 0)

#define ITIP_MASK_SSPFSSIN		 (0x1UL << 1)

#define ITIP_MASK_SSPCLKIN		 (0x1UL << 2)

#define ITIP_MASK_RXDMAC		 (0x1UL << 3)

#define ITIP_MASK_TXDMAC		 (0x1UL << 4)

#define ITIP_MASK_SSPTXDIN		 (0x1UL << 5)

/*
 * SSP Integration Test output Register - SSP_ITOP
 */

#define ITOP_MASK_SSPTXD		 (0x1UL << 0)

#define ITOP_MASK_SSPFSSOUT		 (0x1UL << 1)

#define ITOP_MASK_SSPCLKOUT		 (0x1UL << 2)

#define ITOP_MASK_SSPOEn		 (0x1UL << 3)

#define ITOP_MASK_SSPCTLOEn		 (0x1UL << 4)

#define ITOP_MASK_RORINTR		 (0x1UL << 5)

#define ITOP_MASK_RTINTR		 (0x1UL << 6)

#define ITOP_MASK_RXINTR		 (0x1UL << 7)

#define ITOP_MASK_TXINTR		 (0x1UL << 8)

#define ITOP_MASK_INTR			 (0x1UL << 9)

#define ITOP_MASK_RXDMABREQ		 (0x1UL << 10)

#define ITOP_MASK_RXDMASREQ		 (0x1UL << 11)

#define ITOP_MASK_TXDMABREQ		 (0x1UL << 12)

#define ITOP_MASK_TXDMASREQ		 (0x1UL << 13)

/*
 * SSP Test Data Register - SSP_TDR
 */

#define TDR_MASK_TESTDATA		(0xFFFFFFFF)

/*
 * Message State
 * we use the spi_message.state (void *) pointer to
 * hold a single state value, that's why all this
 * (void *) casting is done here.
 */

#define STATE_START			((void *) 0)

#define STATE_RUNNING			((void *) 1)

#define STATE_DONE			((void *) 2)

#define STATE_ERROR			((void *) -1)

/*
 * SSP State - Whether Enabled or Disabled
 */

#define SSP_DISABLED			(0)

#define SSP_ENABLED			(1)

/*
 * SSP DMA State - Whether DMA Enabled or Disabled
 */

#define SSP_DMA_DISABLED		(0)

#define SSP_DMA_ENABLED			(1)

/*
 * SSP Clock Defaults
 */

#define SSP_DEFAULT_CLKRATE 0x2

#define SSP_DEFAULT_PRESCALE 0x40

/*
 * SSP Clock Parameter ranges
 */

#define CPSDVR_MIN 0x02

#define CPSDVR_MAX 0xFE

#define SCR_MIN 0x00

#define SCR_MAX 0xFF

/*
 * SSP Interrupt related Macros
 */

#define DEFAULT_SSP_REG_IMSC  0x0UL

#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC

#define ENABLE_ALL_INTERRUPTS ( \
        SSP_IMSC_MASK_RORIM | \
        SSP_IMSC_MASK_RTIM | \
        SSP_IMSC_MASK_RXIM | \
        SSP_IMSC_MASK_TXIM \
)


#define CLEAR_ALL_INTERRUPTS  0x3


#define SPI_POLLING_TIMEOUT 1000

/*
 * The type of reading going on on this chip
 */

enum ssp_reading {
	
READING_NULL,
	
READING_U8,
	
READING_U16,
	
READING_U32
};

/**
 * The type of writing going on on this chip
 */

enum ssp_writing {
	
WRITING_NULL,
	
WRITING_U8,
	
WRITING_U16,
	
WRITING_U32
};

/**
 * struct vendor_data - vendor-specific config parameters
 * for PL022 derivates
 * @fifodepth: depth of FIFOs (both)
 * @max_bpw: maximum number of bits per word
 * @unidir: supports unidirection transfers
 * @extended_cr: 32 bit wide control register 0 with extra
 * features and extra features in CR1 as found in the ST variants
 * @pl023: supports a subset of the ST extensions called "PL023"
 * @internal_cs_ctrl: supports chip select control register
 */

struct vendor_data {
	
int fifodepth;
	
int max_bpw;
	
bool unidir;
	
bool extended_cr;
	
bool pl023;
	
bool loopback;
	
bool internal_cs_ctrl;
};

/**
 * struct pl022 - This is the private SSP driver data structure
 * @adev: AMBA device model hookup
 * @vendor: vendor data for the IP block
 * @phybase: the physical memory where the SSP device resides
 * @virtbase: the virtual memory where the SSP is mapped
 * @clk: outgoing clock "SPICLK" for the SPI bus
 * @master: SPI framework hookup
 * @master_info: controller-specific data from machine setup
 * @pump_transfers: Tasklet used in Interrupt Transfer mode
 * @cur_msg: Pointer to current spi_message being processed
 * @cur_transfer: Pointer to current spi_transfer
 * @cur_chip: pointer to current clients chip(assigned from controller_state)
 * @next_msg_cs_active: the next message in the queue has been examined
 *  and it was found that it uses the same chip select as the previous
 *  message, so we left it active after the previous transfer, and it's
 *  active already.
 * @tx: current position in TX buffer to be read
 * @tx_end: end position in TX buffer to be read
 * @rx: current position in RX buffer to be written
 * @rx_end: end position in RX buffer to be written
 * @read: the type of read currently going on
 * @write: the type of write currently going on
 * @exp_fifo_level: expected FIFO level
 * @dma_rx_channel: optional channel for RX DMA
 * @dma_tx_channel: optional channel for TX DMA
 * @sgt_rx: scattertable for the RX transfer
 * @sgt_tx: scattertable for the TX transfer
 * @dummypage: a dummy page used for driving data on the bus with DMA
 * @cur_cs: current chip select (gpio)
 * @chipselects: list of chipselects (gpios)
 */

struct pl022 {
	
struct amba_device		*adev;
	
struct vendor_data		*vendor;
	
resource_size_t			phybase;
	
void __iomem			*virtbase;
	
struct clk			*clk;
	
struct spi_master		*master;
	
struct pl022_ssp_controller	*master_info;
	/* Message per-transfer pump */
	
struct tasklet_struct		pump_transfers;
	
struct spi_message		*cur_msg;
	
struct spi_transfer		*cur_transfer;
	
struct chip_data		*cur_chip;
	
bool				next_msg_cs_active;
	
void				*tx;
	
void				*tx_end;
	
void				*rx;
	
void				*rx_end;
	
enum ssp_reading		read;
	
enum ssp_writing		write;
	
u32				exp_fifo_level;
	
enum ssp_rx_level_trig		rx_lev_trig;
	
enum ssp_tx_level_trig		tx_lev_trig;
	/* DMA settings */
#ifdef CONFIG_DMA_ENGINE
	
struct dma_chan			*dma_rx_channel;
	
struct dma_chan			*dma_tx_channel;
	
struct sg_table			sgt_rx;
	
struct sg_table			sgt_tx;
	
char				*dummypage;
	
bool				dma_running;
#endif
	
int cur_cs;
	
int *chipselects;
};

/**
 * struct chip_data - To maintain runtime state of SSP for each client chip
 * @cr0: Value of control register CR0 of SSP - on later ST variants this
 *       register is 32 bits wide rather than just 16
 * @cr1: Value of control register CR1 of SSP
 * @dmacr: Value of DMA control Register of SSP
 * @cpsr: Value of Clock prescale register
 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
 * @enable_dma: Whether to enable DMA or not
 * @read: function ptr to be used to read when doing xfer for this chip
 * @write: function ptr to be used to write when doing xfer for this chip
 * @cs_control: chip select callback provided by chip
 * @xfer_type: polling/interrupt/DMA
 *
 * Runtime state of the SSP controller, maintained per chip,
 * This would be set according to the current message that would be served
 */

struct chip_data {
	
u32 cr0;
	
u16 cr1;
	
u16 dmacr;
	
u16 cpsr;
	
u8 n_bytes;
	
bool enable_dma;
	
enum ssp_reading read;
	
enum ssp_writing write;
	
void (*cs_control) (u32 command);
	
int xfer_type;
};

/**
 * null_cs_control - Dummy chip select function
 * @command: select/delect the chip
 *
 * If no chip select function is provided by client this is used as dummy
 * chip select
 */

static void null_cs_control(u32 command) { pr_debug("pl022: dummy chip select control, CS=0x%x\n", command); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij16100.00%1100.00%
Total16100.00%1100.00%

/** * internal_cs_control - Control chip select signals via SSP_CSR. * @pl022: SSP driver private data structure * @command: select/delect the chip * * Used on controller with internal chip select control via SSP_CSR register * (vendor extension). Each of the 5 LSB in the register controls one chip * select signal. */
static void internal_cs_control(struct pl022 *pl022, u32 command) { u32 tmp; tmp = readw(SSP_CSR(pl022->virtbase)); if (command == SSP_CHIP_SELECT) tmp &= ~BIT(pl022->cur_cs); else tmp |= BIT(pl022->cur_cs); writew(tmp, SSP_CSR(pl022->virtbase)); }

Contributors

PersonTokensPropCommitsCommitProp
anders berganders berg67100.00%1100.00%
Total67100.00%1100.00%


static void pl022_cs_control(struct pl022 *pl022, u32 command) { if (pl022->vendor->internal_cs_ctrl) internal_cs_control(pl022, command); else if (gpio_is_valid(pl022->cur_cs)) gpio_set_value(pl022->cur_cs, command); else pl022->cur_chip->cs_control(command); }

Contributors

PersonTokensPropCommitsCommitProp
roland stiggeroland stigge4272.41%150.00%
anders berganders berg1627.59%150.00%
Total58100.00%2100.00%

/** * giveback - current spi_message is over, schedule next message and call * callback of this message. Assumes that caller already * set message->status; dma and pio irqs are blocked * @pl022: SSP driver private data structure */
static void giveback(struct pl022 *pl022) { struct spi_transfer *last_transfer; pl022->next_msg_cs_active = false; last_transfer = list_last_entry(&pl022->cur_msg->transfers, struct spi_transfer, transfer_list); /* Delay if requested before any change in chip select */ if (last_transfer->delay_usecs) /* * FIXME: This runs in interrupt context. * Is this really smart? */ udelay(last_transfer->delay_usecs); if (!last_transfer->cs_change) { struct spi_message *next_msg; /* * cs_change was not set. We can keep the chip select * enabled if there is message in the queue and it is * for the same spi device. * * We cannot postpone this until pump_messages, because * after calling msg->complete (below) the driver that * sent the current message could be unloaded, which * could invalidate the cs_control() callback... */ /* get a pointer to the next message, if any */ next_msg = spi_get_next_queued_message(pl022->master); /* * see if the next and current messages point * to the same spi device. */ if (next_msg && next_msg->spi != pl022->cur_msg->spi) next_msg = NULL; if (!next_msg || pl022->cur_msg->state == STATE_ERROR) pl022_cs_control(pl022, SSP_CHIP_DESELECT); else pl022->next_msg_cs_active = true; } pl022->cur_msg = NULL; pl022->cur_transfer = NULL; pl022->cur_chip = NULL; /* disable the SPI/SSP operation */ writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase)); spi_finalize_current_message(pl022->master); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij10056.18%228.57%
virupax sadashivpetimathvirupax sadashivpetimath6637.08%228.57%
alexander sverdlinalexander sverdlin73.93%114.29%
roland stiggeroland stigge31.69%114.29%
axel linaxel lin21.12%114.29%
Total178100.00%7100.00%

/** * flush - flush the FIFO to reach a clean state * @pl022: SSP driver private data structure */
static int flush(struct pl022 *pl022) { unsigned long limit = loops_per_jiffy << 1; dev_dbg(&pl022->adev->dev, "flush\n"); do { while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE) readw(SSP_DR(pl022->virtbase)); } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--); pl022->exp_fifo_level = 0; return limit; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij87100.00%2100.00%
Total87100.00%2100.00%

/** * restore_state - Load configuration of current chip * @pl022: SSP driver private data structure */
static void restore_state(struct pl022 *pl022) { struct chip_data *chip = pl022->cur_chip; if (pl022->vendor->extended_cr) writel(chip->cr0, SSP_CR0(pl022->virtbase)); else writew(chip->cr0, SSP_CR0(pl022->virtbase)); writew(chip->cr1, SSP_CR1(pl022->virtbase)); writew(chip->dmacr, SSP_DMACR(pl022->virtbase)); writew(chip->cpsr, SSP_CPSR(pl022->virtbase)); writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase)); writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij123100.00%2100.00%
Total123100.00%2100.00%

/* * Default SSP Register Values */ #define DEFAULT_SSP_REG_CR0 ( \ GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \ GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \ GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \ GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \ GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \ ) /* ST versions have slightly different bit layout */ #define DEFAULT_SSP_REG_CR0_ST ( \ GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \ GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \ GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \ GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \ GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \ GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \ GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \ ) /* The PL023 version is slightly different again */ #define DEFAULT_SSP_REG_CR0_ST_PL023 ( \ GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \ GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \ GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \ GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \ ) #define DEFAULT_SSP_REG_CR1 ( \ GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \ GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \ GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \ GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \ ) /* ST versions extend this register to use all 16 bits */ #define DEFAULT_SSP_REG_CR1_ST ( \ DEFAULT_SSP_REG_CR1 | \ GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \ GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \ GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\ GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \ GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \ ) /* * The PL023 variant has further differences: no loopback mode, no microwire * support, and a new clock feedback delay setting. */ #define DEFAULT_SSP_REG_CR1_ST_PL023 ( \ GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \ GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \ GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \ GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \ GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \ GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \ GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \ GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \ ) #define DEFAULT_SSP_REG_CPSR ( \ GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \ ) #define DEFAULT_SSP_REG_DMACR (\ GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \ GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \ ) /** * load_ssp_default_config - Load default configuration for SSP * @pl022: SSP driver private data structure */
static void load_ssp_default_config(struct pl022 *pl022) { if (pl022->vendor->pl023) { writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase)); writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase)); } else if (pl022->vendor->extended_cr) { writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase)); writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase)); } else { writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase)); writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase)); } writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase)); writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase)); writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase)); writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij155100.00%3100.00%
Total155100.00%3100.00%

/** * This will write to TX and read from RX according to the parameters * set in pl022. */
static void readwriter(struct pl022 *pl022) { /* * The FIFO depth is different between primecell variants. * I believe filling in too much in the FIFO might cause * errons in 8bit wide transfers on ARM variants (just 8 words * FIFO, means only 8x8 = 64 bits in FIFO) at least. * * To prevent this issue, the TX FIFO is only filled to the * unused RX FIFO fill length, regardless of what the TX * FIFO status flag indicates. */ dev_dbg(&pl022->adev->dev, "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n", __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end); /* Read as much as you can */ while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE) && (pl022->rx < pl022->rx_end)) { switch (pl022->read) { case READING_NULL: readw(SSP_DR(pl022->virtbase)); break; case READING_U8: *(u8 *) (pl022->rx) = readw(SSP_DR(pl022->virtbase)) & 0xFFU; break; case READING_U16: *(u16 *) (pl022->rx) = (u16) readw(SSP_DR(pl022->virtbase)); break; case READING_U32: *(u32 *) (pl022->rx) = readl(SSP_DR(pl022->virtbase)); break; } pl022->rx += (pl022->cur_chip->n_bytes); pl022->exp_fifo_level--; } /* * Write as much as possible up to the RX FIFO size */ while ((pl022->exp_fifo_level < pl022->vendor->fifodepth) && (pl022->tx < pl022->tx_end)) { switch (pl022->write) { case WRITING_NULL: writew(0x0, SSP_DR(pl022->virtbase)); break; case WRITING_U8: writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase)); break; case WRITING_U16: writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase)); break; case WRITING_U32: writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase)); break; } pl022->tx += (pl022->cur_chip->n_bytes); pl022->exp_fifo_level++; /* * This inner reader takes care of things appearing in the RX * FIFO as we're transmitting. This will happen a lot since the * clock starts running when you put things into the TX FIFO, * and then things are continuously clocked into the RX FIFO. */ while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE) && (pl022->rx < pl022->rx_end)) { switch (pl022->read) { case READING_NULL: readw(SSP_DR(pl022->virtbase)); break; case READING_U8: *(u8 *) (pl022->rx) = readw(SSP_DR(pl022->virtbase)) & 0xFFU; break; case READING_U16: *(u16 *) (pl022->rx) = (u16) readw(SSP_DR(pl022->virtbase)); break; case READING_U32: *(u32 *) (pl022->rx) = readl(SSP_DR(pl022->virtbase)); break; } pl022->rx += (pl022->cur_chip->n_bytes); pl022->exp_fifo_level--; } } /* * When we exit here the TX FIFO should be full and the RX FIFO * should be empty */ }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij48299.59%266.67%
lucas de marchilucas de marchi20.41%133.33%
Total484100.00%3100.00%

/** * next_transfer - Move to the Next transfer in the current spi message * @pl022: SSP driver private data structure * * This function moves though the linked list of spi transfers in the * current spi message and returns with the state of current spi * message i.e whether its last transfer is done(STATE_DONE) or * Next transfer is ready(STATE_RUNNING) */
static void *next_transfer(struct pl022 *pl022) { struct spi_message *msg = pl022->cur_msg; struct spi_transfer *trans = pl022->cur_transfer; /* Move to next transfer */ if (trans->transfer_list.next != &msg->transfers) { pl022->cur_transfer = list_entry(trans->transfer_list.next, struct spi_transfer, transfer_list); return STATE_RUNNING; } return STATE_DONE; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij70100.00%1100.00%
Total70100.00%1100.00%

/* * This DMA functionality is only compiled in if we have * access to the generic DMA devices/DMA engine. */ #ifdef CONFIG_DMA_ENGINE
static void unmap_free_dma_scatter(struct pl022 *pl022) { /* Unmap and free the SG tables */ dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl, pl022->sgt_tx.nents, DMA_TO_DEVICE); dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl, pl022->sgt_rx.nents, DMA_FROM_DEVICE); sg_free_table(&pl022->sgt_rx); sg_free_table(&pl022->sgt_tx); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij78100.00%3100.00%
Total78100.00%3100.00%


static void dma_callback(void *data) { struct pl022 *pl022 = data; struct spi_message *msg = pl022->cur_msg; BUG_ON(!pl022->sgt_rx.sgl); #ifdef VERBOSE_DEBUG /* * Optionally dump out buffers to inspect contents, this is * good if you want to convince yourself that the loopback * read/write contents are the same, when adopting to a new * DMA engine. */ { struct scatterlist *sg; unsigned int i; dma_sync_sg_for_cpu(&pl022->adev->dev, pl022->sgt_rx.sgl, pl022->sgt_rx.nents, DMA_FROM_DEVICE); for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) { dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i); print_hex_dump(KERN_ERR, "SPI RX: ", DUMP_PREFIX_OFFSET, 16, 1, sg_virt(sg), sg_dma_len(sg), 1); } for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) { dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i); print_hex_dump(KERN_ERR, "SPI TX: ", DUMP_PREFIX_OFFSET, 16, 1, sg_virt(sg), sg_dma_len(sg), 1); } } #endif unmap_free_dma_scatter(pl022); /* Update total bytes transferred */ msg->actual_length += pl022->cur_transfer->len; if (pl022->cur_transfer->cs_change) pl022_cs_control(pl022, SSP_CHIP_DESELECT); /* Move to next transfer */ msg->state = next_transfer(pl022); tasklet_schedule(&pl022->pump_transfers); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij22498.25%250.00%
roland stiggeroland stigge31.32%125.00%
lucas de marchilucas de marchi10.44%125.00%
Total228100.00%4100.00%


static void setup_dma_scatter(struct pl022 *pl022, void *buffer, unsigned int length, struct sg_table *sgtab) { struct scatterlist *sg; int bytesleft = length; void *bufp = buffer; int mapbytes; int i; if (buffer) { for_each_sg(sgtab->sgl, sg, sgtab->nents, i) { /* * If there are less bytes left than what fits * in the current page (plus page alignment offset) * we just feed in this, else we stuff in as much * as we can. */ if (bytesleft < (PAGE_SIZE - offset_in_page(bufp))) mapbytes = bytesleft; else mapbytes = PAGE_SIZE - offset_in_page(bufp); sg_set_page(sg, virt_to_page(bufp), mapbytes, offset_in_page(bufp)); bufp += mapbytes; bytesleft -= mapbytes; dev_dbg(&pl022->adev->dev, "set RX/TX target page @ %p, %d bytes, %d left\n", bufp, mapbytes, bytesleft); } } else { /* Map the dummy buffer on every page */ for_each_sg(sgtab->sgl, sg, sgtab->nents, i) { if (bytesleft < PAGE_SIZE) mapbytes = bytesleft; else mapbytes = PAGE_SIZE; sg_set_page(sg, virt_to_page(pl022->dummypage), mapbytes, 0); bytesleft -= mapbytes; dev_dbg(&pl022->adev->dev, "set RX/TX to dummy page %d bytes, %d left\n", mapbytes, bytesleft); } } BUG_ON(bytesleft); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij207100.00%1100.00%
Total207100.00%1100.00%

/** * configure_dma - configures the channels for the next transfer * @pl022: SSP driver's private data structure */
static int configure_dma(struct pl022 *pl022) { struct dma_slave_config rx_conf = { .src_addr = SSP_DR(pl022->phybase), .direction = DMA_DEV_TO_MEM, .device_fc = false, }; struct dma_slave_config tx_conf = { .dst_addr = SSP_DR(pl022->phybase), .direction = DMA_MEM_TO_DEV, .device_fc = false, }; unsigned int pages; int ret; int rx_sglen, tx_sglen; struct dma_chan *rxchan = pl022->dma_rx_channel; struct dma_chan *txchan = pl022->dma_tx_channel; struct dma_async_tx_descriptor *rxdesc; struct dma_async_tx_descriptor *txdesc; /* Check that the channels are available */ if (!rxchan || !txchan) return -ENODEV; /* * If supplied, the DMA burstsize should equal the FIFO trigger level. * Notice that the DMA engine uses one-to-one mapping. Since we can * not trigger on 2 elements this needs explicit mapping rather than * calculation. */ switch (pl022->rx_lev_trig) { case SSP_RX_1_OR_MORE_ELEM: rx_conf.src_maxburst = 1; break; case SSP_RX_4_OR_MORE_ELEM: rx_conf.src_maxburst = 4; break; case SSP_RX_8_OR_MORE_ELEM: rx_conf.src_maxburst = 8; break; case SSP_RX_16_OR_MORE_ELEM: rx_conf.src_maxburst = 16; break; case SSP_RX_32_OR_MORE_ELEM: rx_conf.src_maxburst = 32; break; default: rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1; break; } switch (pl022->tx_lev_trig) { case SSP_TX_1_OR_MORE_EMPTY_LOC: tx_conf.dst_maxburst = 1; break; case SSP_TX_4_OR_MORE_EMPTY_LOC: tx_conf.dst_maxburst = 4; break; case SSP_TX_8_OR_MORE_EMPTY_LOC: tx_conf.dst_maxburst = 8; break; case SSP_TX_16_OR_MORE_EMPTY_LOC: tx_conf.dst_maxburst = 16; break; case SSP_TX_32_OR_MORE_EMPTY_LOC: tx_conf.dst_maxburst = 32; break; default: tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1; break; } switch (pl022->read) { case READING_NULL: /* Use the same as for writing */ rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED; break; case READING_U8: rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; break; case READING_U16: rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; break; case READING_U32: rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; break; } switch (pl022->write) { case WRITING_NULL: /* Use the same as for reading */ tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED; break; case WRITING_U8: tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; break; case WRITING_U16: tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; break; case WRITING_U32: tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; break; } /* SPI pecularity: we need to read and write the same width */ if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) rx_conf.src_addr_width = tx_conf.dst_addr_width; if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) tx_conf.dst_addr_width = rx_conf.src_addr_width; BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width); dmaengine_slave_config(rxchan, &rx_conf); dmaengine_slave_config(txchan, &tx_conf); /* Create sglists for the transfers */ pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE); dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages); ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC); if (ret) goto err_alloc_rx_sg; ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC); if (ret) goto err_alloc_tx_sg; /* Fill in the scatterlists for the RX+TX buffers */ setup_dma_scatter(pl022, pl022->rx, pl022->cur_transfer->len, &pl022->sgt_rx); setup_dma_scatter(pl022, pl022->tx, pl022->cur_transfer->len, &pl022->sgt_tx); /* Map DMA buffers */ rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl, pl022->sgt_rx.nents, DMA_FROM_DEVICE); if (!rx_sglen) goto err_rx_sgmap; tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl, pl022->sgt_tx.nents, DMA_TO_DEVICE); if (!tx_sglen) goto err_tx_sgmap; /* Send both scatterlists */ rxdesc = dmaengine_prep_slave_sg(rxchan, pl022->sgt_rx.sgl, rx_sglen, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!rxdesc) goto err_rxdesc; txdesc = dmaengine_prep_slave_sg(txchan, pl022->sgt_tx.sgl, tx_sglen, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!txdesc) goto err_txdesc; /* Put the callback on the RX transfer only, that should finish last */ rxdesc->callback = dma_callback; rxdesc->callback_param = pl022; /* Submit and fire RX and TX with TX last so we're ready to read! */ dmaengine_submit(rxdesc); dmaengine_submit(txdesc); dma_async_issue_pending(rxchan); dma_async_issue_pending(txchan); pl022->dma_running = true; return 0; err_txdesc: dmaengine_terminate_all(txchan); err_rxdesc: dmaengine_terminate_all(rxchan); dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl, pl022->sgt_tx.nents, DMA_TO_DEVICE); err_tx_sgmap: dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl, pl022->sgt_rx.nents, DMA_FROM_DEVICE); err_rx_sgmap: sg_free_table(&pl022->sgt_tx); err_alloc_tx_sg: sg_free_table(&pl022->sgt_rx); err_alloc_rx_sg: return -ENOMEM; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij76396.95%650.00%
viresh kumarviresh kumar172.16%325.00%
vinod koulvinod koul40.51%18.33%
alexandre bouninealexandre bounine20.25%18.33%
ray juiray jui10.13%18.33%
Total787100.00%12100.00%


static int pl022_dma_probe(struct pl022 *pl022) { dma_cap_mask_t mask; /* Try to acquire a generic DMA engine slave channel */ dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); /* * We need both RX and TX channels to do DMA, else do none * of them. */ pl022->dma_rx_channel = dma_request_channel(mask, pl022->master_info->dma_filter, pl022->master_info->dma_rx_param); if (!pl022->dma_rx_channel) { dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n"); goto err_no_rxchan; } pl022->dma_tx_channel = dma_request_channel(mask, pl022->master_info->dma_filter, pl022->master_info->dma_tx_param); if (!pl022->dma_tx_channel) { dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n"); goto err_no_txchan; } pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL); if (!pl022->dummypage) goto err_no_dummypage; dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n", dma_chan_name(pl022->dma_rx_channel), dma_chan_name(pl022->dma_tx_channel)); return 0; err_no_dummypage: dma_release_channel(pl022->dma_tx_channel); err_no_txchan: dma_release_channel(pl022->dma_rx_channel); pl022->dma_rx_channel = NULL; err_no_rxchan: dev_err(&pl022->adev->dev, "Failed to work in dma mode, work without dma!\n"); return -ENODEV; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij19693.33%150.00%
viresh kumarviresh kumar146.67%150.00%
Total210100.00%2100.00%


static int pl022_dma_autoprobe(struct pl022 *pl022) { struct device *dev = &pl022->adev->dev; struct dma_chan *chan; int err; /* automatically configure DMA channels from platform, normally using DT */ chan = dma_request_slave_channel_reason(dev, "rx"); if (IS_ERR(chan)) { err = PTR_ERR(chan); goto err_no_rxchan; } pl022->dma_rx_channel = chan; chan = dma_request_slave_channel_reason(dev, "tx"); if (IS_ERR(chan)) { err = PTR_ERR(chan); goto err_no_txchan; } pl022->dma_tx_channel = chan; pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL); if (!pl022->dummypage) { err = -ENOMEM; goto err_no_dummypage; } return 0; err_no_dummypage: dma_release_channel(pl022->dma_tx_channel); pl022->dma_tx_channel = NULL; err_no_txchan: dma_release_channel(pl022->dma_rx_channel); pl022->dma_rx_channel = NULL; err_no_rxchan: return err; }

Contributors

PersonTokensPropCommitsCommitProp
arnd bergmannarnd bergmann11066.27%150.00%
rabin vincentrabin vincent5633.73%150.00%
Total166100.00%2100.00%


static void terminate_dma(struct pl022 *pl022) { struct dma_chan *rxchan = pl022->dma_rx_channel; struct dma_chan *txchan = pl022->dma_tx_channel; dmaengine_terminate_all(rxchan); dmaengine_terminate_all(txchan); unmap_free_dma_scatter(pl022); pl022->dma_running = false; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij50100.00%3100.00%
Total50100.00%3100.00%


static void pl022_dma_remove(struct pl022 *pl022) { if (pl022->dma_running) terminate_dma(pl022); if (pl022->dma_tx_channel) dma_release_channel(pl022->dma_tx_channel); if (pl022->dma_rx_channel) dma_release_channel(pl022->dma_rx_channel); kfree(pl022->dummypage); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij55100.00%2100.00%
Total55100.00%2100.00%

#else
static inline int configure_dma(struct pl022 *pl022) { return -ENODEV; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij16100.00%1100.00%
Total16100.00%1100.00%


static inline int pl022_dma_autoprobe(struct pl022 *pl022) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
arnd bergmannarnd bergmann15100.00%1100.00%
Total15100.00%1100.00%


static inline int pl022_dma_probe(struct pl022 *pl022) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij15100.00%1100.00%
Total15100.00%1100.00%


static inline void pl022_dma_remove(struct pl022 *pl022) { }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij11100.00%1100.00%
Total11100.00%1100.00%

#endif /** * pl022_interrupt_handler - Interrupt handler for SSP controller * * This function handles interrupts generated for an interrupt based transfer. * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the * current message's state as STATE_ERROR and schedule the tasklet * pump_transfers which will do the postprocessing of the current message by * calling giveback(). Otherwise it reads data from RX FIFO till there is no * more data, and writes data in TX FIFO till it is not full. If we complete * the transfer we move to the next transfer and schedule the tasklet. */
static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id) { struct pl022 *pl022 = dev_id; struct spi_message *msg = pl022->cur_msg; u16 irq_status = 0; if (unlikely(!msg)) { dev_err(&pl022->adev->dev, "bad message state in interrupt handler"); /* Never fail */ return IRQ_HANDLED; } /* Read the Interrupt Status Register */ irq_status = readw(SSP_MIS(pl022->virtbase)); if (unlikely(!irq_status)) return IRQ_NONE; /* * This handles the FIFO interrupts, the timeout * interrupts are flatly ignored, they cannot be * trusted. */ if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) { /* * Overrun interrupt - bail out since our Data has been * corrupted */ dev_err(&pl022->adev->dev, "FIFO overrun\n"); if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF) dev_err(&pl022->adev->dev, "RXFIFO is full\n"); /* * Disable and clear interrupts, disable SSP, * mark message with bad status so it can be * retried. */ writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase)); writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase)); msg->state = STATE_ERROR; /* Schedule message queue handler */ tasklet_schedule(&pl022->pump_transfers); return IRQ_HANDLED; } readwriter(pl022); if (pl022->tx == pl022->tx_end) { /* Disable Transmit interrupt, enable receive interrupt */ writew((readw(SSP_IMSC(pl022->virtbase)) & ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase)); } /* * Since all transactions must write as much as shall be read, * we can conclude the entire transaction once RX is complete. * At this point, all TX will always be finished. */ if (pl022->rx >= pl022->rx_end) { writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase)); writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase)); if (unlikely(pl022->rx > pl022->rx_end)) { dev_warn(&pl022->adev->dev, "read %u surplus " "bytes (did you request an odd " "number of bytes on a 16bit bus?)\n", (u32) (pl022->rx - pl022->rx_end)); } /* Update total bytes transferred */ msg->actual_length += pl022->cur_transfer->len; if (pl022->cur_transfer->cs_change) pl022_cs_control(pl022, SSP_CHIP_DESELECT); /* Move to next transfer */ msg->state = next_transfer(pl022); tasklet_schedule(&pl022->pump_transfers); return IRQ_HANDLED; } return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij37197.89%240.00%
chris blairchris blair41.06%120.00%
roland stiggeroland stigge30.79%120.00%
lucas de marchilucas de marchi10.26%120.00%
Total379100.00%5100.00%

/** * This sets up the pointers to memory for the next message to * send out on the SPI bus. */
static int set_up_next_transfer(struct pl022 *pl022, struct spi_transfer *transfer) { int residue; /* Sanity check the message for this bus width */ residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes; if (unlikely(residue != 0)) { dev_err(&pl022->adev->dev, "message of %u bytes to transmit but the current " "chip bus has a data width of %u bytes!\n", pl022->cur_transfer->len, pl022->cur_chip->n_bytes); dev_err(&pl022->adev->dev, "skipping this message\n"); return -EIO; } pl022->tx = (void *)transfer->tx_buf; pl022->tx_end = pl022->tx + pl022->cur_transfer->len; pl022->rx = (void *)transfer->rx_buf; pl022->rx_end = pl022->rx + pl022->cur_transfer->len; pl022->write = pl022->tx ? pl022->cur_chip->write : WRITING_NULL; pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij173100.00%1100.00%
Total173100.00%1100.00%

/** * pump_transfers - Tasklet function which schedules next transfer * when running in interrupt or DMA transfer mode. * @data: SSP driver private data structure * */
static void pump_transfers(unsigned long data) { struct pl022 *pl022 = (struct pl022 *) data; struct spi_message *message = NULL; struct spi_transfer *transfer = NULL; struct spi_transfer *previous = NULL; /* Get current state information */ message = pl022->cur_msg; transfer = pl022->cur_transfer; /* Handle for abort */ if (message->state == STATE_ERROR) { message->status = -EIO; giveback(pl022); return; } /* Handle end of message */ if (message->state == STATE_DONE) { message->status = 0; giveback(pl022); return; } /* Delay if requested at end of transfer before CS change */ if (message->state == STATE_RUNNING) { previous = list_entry(transfer->transfer_list.prev, struct spi_transfer, transfer_list); if (previous->delay_usecs) /* * FIXME: This runs in interrupt context. * Is this really smart? */ udelay(previous->delay_usecs); /* Reselect chip select only if cs_change was requested */ if (previous->cs_change) pl022_cs_control(pl022, SSP_CHIP_SELECT); } else { /* STATE_START */ message->state = STATE_RUNNING; } if (set_up_next_transfer(pl022, transfer)) { message->state = STATE_ERROR; message->status = -EIO; giveback(pl022); return; } /* Flush the FIFOs and let's go! */ flush(pl022); if (pl022->cur_chip->enable_dma) { if (configure_dma(pl022)) { dev_dbg(&pl022->adev->dev, "configuration of DMA failed, fall back to interrupt mode\n"); goto err_config_dma; } return; } err_config_dma: /* enable all interrupts except RX */ writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase)); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij24996.89%240.00%
chris blairchris blair41.56%120.00%
roland stiggeroland stigge31.17%120.00%
virupax sadashivpetimathvirupax sadashivpetimath10.39%120.00%
Total257100.00%5100.00%


static void do_interrupt_dma_transfer(struct pl022 *pl022) { /* * Default is to enable all interrupts except RX - * this will be enabled once TX is complete */ u32 irqflags = (u32)(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM); /* Enable target chip, if not already active */ if (!pl022->next_msg_cs_active) pl022_cs_control(pl022, SSP_CHIP_SELECT); if (set_up_next_transfer(pl022, pl022->cur_transfer)) { /* Error path */ pl022->cur_msg->state = STATE_ERROR; pl022->cur_msg->status = -EIO; giveback(pl022); return; } /* If we're using DMA, set up DMA here */ if (pl022->cur_chip->enable_dma) { /* Configure DMA transfer */ if (configure_dma(pl022)) { dev_dbg(&pl022->adev->dev, "configuration of DMA failed, fall back to interrupt mode\n"); goto err_config_dma; } /* Disable interrupts in DMA mode, IRQ from DMA controller */ irqflags = DISABLE_ALL_INTERRUPTS; } err_config_dma: /* Enable SSP, turn on interrupts */ writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE), SSP_CR1(pl022->virtbase)); writew(irqflags, SSP_IMSC(pl022->virtbase)); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij13787.26%233.33%
virupax sadashivpetimathvirupax sadashivpetimath85.10%116.67%
mark brownmark brown53.18%116.67%
chris blairchris blair42.55%116.67%
roland stiggeroland stigge31.91%116.67%
Total157100.00%6100.00%


static void do_polling_transfer(struct pl022 *pl022) { struct spi_message *message = NULL; struct spi_transfer *transfer = NULL; struct spi_transfer *previous = NULL; struct chip_data *chip; unsigned long time, timeout; chip = pl022->cur_chip; message = pl022->cur_msg; while (message->state != STATE_DONE) { /* Handle for abort */ if (message->state == STATE_ERROR) break; transfer = pl022->cur_transfer; /* Delay if requested at end of transfer */ if (message->state == STATE_RUNNING) { previous = list_entry(transfer->transfer_list.prev, struct spi_transfer, transfer_list); if (previous->delay_usecs) udelay(previous->delay_usecs); if (previous->cs_change) pl022_cs_control(pl022, SSP_CHIP_SELECT); } else { /* STATE_START */ message->state = STATE_RUNNING; if (!pl022->next_msg_cs_active) pl022_cs_control(pl022, SSP_CHIP_SELECT); } /* Configuration Changing Per Transfer */ if (set_up_next_transfer(pl022, transfer)) { /* Error path */ message->state = STATE_ERROR; break; } /* Flush FIFOs and enable SSP */ flush(pl022); writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE), SSP_CR1(pl022->virtbase)); dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n"); timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT); while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) { time = jiffies; readwriter(pl022); if (time_after(time, timeout)) { dev_warn(&pl022->adev->dev, "%s: timeout!\n", __func__); message->state = STATE_ERROR; goto out; } cpu_relax(); } /* Update total byte transferred */ message->actual_length += pl022->cur_transfer->len; if (pl022->cur_transfer->cs_change) pl022_cs_control(pl022, SSP_CHIP_DESELECT); /* Move to next transfer */ message->state = next_transfer(pl022); } out: /* Handle end of message */ if (message->state == STATE_DONE) message->status = 0; else message->status = -EIO; giveback(pl022); return; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij28879.56%450.00%
magnus templingmagnus templing5715.75%112.50%
roland stiggeroland stigge92.49%112.50%
virupax sadashivpetimathvirupax sadashivpetimath71.93%112.50%
lucas de marchilucas de marchi10.28%112.50%
Total362100.00%8100.00%


static int pl022_transfer_one_message(struct spi_master *master, struct spi_message *msg) { struct pl022 *pl022 = spi_master_get_devdata(master); /* Initial message state */ pl022->cur_msg = msg; msg->state = STATE_START; pl022->cur_transfer = list_entry(msg->transfers.next, struct spi_transfer, transfer_list); /* Setup the SPI using the per chip configuration */ pl022->cur_chip = spi_get_ctldata(msg->spi); pl022->cur_cs = pl022->chipselects[msg->spi->chip_select]; restore_state(pl022); flush(pl022); if (pl022->cur_chip->xfer_type == POLLING_TRANSFER) do_polling_transfer(pl022); else do_interrupt_dma_transfer(pl022); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij7765.25%233.33%
chris blairchris blair1815.25%233.33%
roland stiggeroland stigge1512.71%116.67%
virupax sadashivpetimathvirupax sadashivpetimath86.78%116.67%
Total118100.00%6100.00%


static int pl022_unprepare_transfer_hardware(struct spi_master *master) { struct pl022 *pl022 = spi_master_get_devdata(master); /* nothing more to do - disable spi/ssp and power off */ writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase)); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij52100.00%2100.00%
Total52100.00%2100.00%


static int verify_controller_parameters(struct pl022 *pl022, struct pl022_config_chip const *chip_info) { if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI) || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) { dev_err(&pl022->adev->dev, "interface is configured incorrectly\n"); return -EINVAL; } if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) && (!pl022->vendor->unidir)) { dev_err(&pl022->adev->dev, "unidirectional mode not supported in this " "hardware version\n"); return -EINVAL; } if ((chip_info->hierarchy != SSP_MASTER) && (chip_info->hierarchy != SSP_SLAVE)) { dev_err(&pl022->adev->dev, "hierarchy is configured incorrectly\n"); return -EINVAL; } if ((chip_info->com_mode != INTERRUPT_TRANSFER) && (chip_info->com_mode != DMA_TRANSFER) && (chip_info->com_mode != POLLING_TRANSFER)) { dev_err(&pl022->adev->dev, "Communication mode is configured incorrectly\n"); return -EINVAL; } switch (chip_info->rx_lev_trig) { case SSP_RX_1_OR_MORE_ELEM: case SSP_RX_4_OR_MORE_ELEM: case SSP_RX_8_OR_MORE_ELEM: /* These are always OK, all variants can handle this */ break; case SSP_RX_16_OR_MORE_ELEM: if (pl022->vendor->fifodepth < 16) { dev_err(&pl022->adev->dev, "RX FIFO Trigger Level is configured incorrectly\n"); return -EINVAL; } break; case SSP_RX_32_OR_MORE_ELEM: if (pl022->vendor->fifodepth < 32) { dev_err(&pl022->adev->dev, "RX FIFO Trigger Level is configured incorrectly\n"); return -EINVAL; } break; default: dev_err(&pl022->adev->dev, "RX FIFO Trigger Level is configured incorrectly\n"); return -EINVAL; } switch (chip_info->tx_lev_trig) { case SSP_TX_1_OR_MORE_EMPTY_LOC: case SSP_TX_4_OR_MORE_EMPTY_LOC: case SSP_TX_8_OR_MORE_EMPTY_LOC: /* These are always OK, all variants can handle this */ break; case SSP_TX_16_OR_MORE_EMPTY_LOC: if (pl022->vendor->fifodepth < 16) { dev_err(&pl022->adev->dev, "TX FIFO Trigger Level is configured incorrectly\n"); return -EINVAL; } break; case SSP_TX_32_OR_MORE_EMPTY_LOC: if (pl022->vendor->fifodepth < 32) { dev_err(&pl022->adev->dev, "TX FIFO Trigger Level is configured incorrectly\n"); return -EINVAL; } break; default: dev_err(&pl022->adev->dev, "TX FIFO Trigger Level is configured incorrectly\n"); return -EINVAL; } if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) { if ((chip_info->ctrl_len < SSP_BITS_4) || (chip_info->ctrl_len > SSP_BITS_32)) { dev_err(&pl022->adev->dev, "CTRL LEN is configured incorrectly\n"); return -EINVAL; } if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO) && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) { dev_err(&pl022->adev->dev, "Wait State is configured incorrectly\n"); return -EINVAL; } /* Half duplex is only available in the ST Micro version */ if (pl022->vendor->extended_cr) { if ((chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX) && (chip_info->duplex != SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) { dev_err(&pl022->adev->dev, "Microwire duplex mode is configured incorrectly\n"); return -EINVAL; } } else { if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX) dev_err(&pl022->adev->dev, "Microwire half duplex mode requested," " but this is only available in the" " ST version of PL022\n"); return -EINVAL; } } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij53099.62%583.33%
julia lawalljulia lawall20.38%116.67%
Total532100.00%6100.00%


static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr) { return rate / (cpsdvsr * (1 + scr)); }

Contributors

PersonTokensPropCommitsCommitProp
viresh kumarviresh kumar29100.00%1100.00%
Total29100.00%1100.00%


static int calculate_effective_freq(struct pl022 *pl022, int freq, struct ssp_clock_params * clk_freq) { /* Lets calculate the frequency parameters */ u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN; u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0, best_scr = 0, tmp, found = 0; rate = clk_get_rate(pl022->clk); /* cpsdvscr = 2 & scr 0 */ max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN); /* cpsdvsr = 254 & scr = 255 */ min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX); if (freq > max_tclk) dev_warn(&pl022->adev->dev, "Max speed that can be programmed is %d Hz, you requested %d\n", max_tclk, freq); if (freq < min_tclk) { dev_err(&pl022->adev->dev, "Requested frequency: %d Hz is less than minimum possible %d Hz\n", freq, min_tclk); return -EINVAL; } /* * best_freq will give closest possible available rate (<= requested * freq) for all values of scr & cpsdvsr. */ while ((cpsdvsr <= CPSDVR_MAX) && !found) { while (scr <= SCR_MAX) { tmp = spi_rate(rate, cpsdvsr, scr); if (tmp > freq) { /* we need lower freq */ scr++; continue; } /* * If found exact value, mark found and break. * If found more closer value, update and break. */ if (tmp > best_freq) { best_freq = tmp; best_cpsdvsr = cpsdvsr; best_scr = scr; if (tmp == freq) found = 1; } /* * increased scr will give lower rates, which are not * required */ break; } cpsdvsr += 2; scr = SCR_MIN; } WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n", freq); clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF); clk_freq->scr = (u8) (best_scr & 0xFF); dev_dbg(&pl022->adev->dev, "SSP Target Frequency is: %u, Effective Frequency is %u\n", freq, best_freq); dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n", clk_freq->cpsdvsr, clk_freq->scr); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij15752.51%125.00%
viresh kumarviresh kumar14247.49%375.00%
Total299100.00%4100.00%

/* * A piece of default chip info unless the platform * supplies it. */ static const struct pl022_config_chip pl022_default_chip_info = { .com_mode = POLLING_TRANSFER, .iface = SSP_INTERFACE_MOTOROLA_SPI, .hierarchy = SSP_SLAVE, .slave_tx_disable = DO_NOT_DRIVE_TX, .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM, .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC, .ctrl_len = SSP_BITS_8, .wait_state = SSP_MWIRE_WAIT_ZERO, .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, .cs_control = null_cs_control, }; /** * pl022_setup - setup function registered to SPI master framework * @spi: spi device which is requesting setup * * This function is registered to the SPI framework for this SPI master * controller. If it is the first time when setup is called by this device, * this function will initialize the runtime state for this chip and save * the same in the device structure. Else it will update the runtime info * with the updated chip info. Nothing is really being written to the * controller hardware here, that is not done until the actual transfer * commence. */
static int pl022_setup(struct spi_device *spi) { struct pl022_config_chip const *chip_info; struct pl022_config_chip chip_info_dt; struct chip_data *chip; struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0}; int status = 0; struct pl022 *pl022 = spi_master_get_devdata(spi->master); unsigned int bits = spi->bits_per_word; u32 tmp; struct device_node *np = spi->dev.of_node; if (!spi->max_speed_hz) return -EINVAL; /* Get controller_state if one is supplied */ chip = spi_get_ctldata(spi); if (chip == NULL) { chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL); if (!chip) return -ENOMEM; dev_dbg(&spi->dev, "allocated memory for controller's runtime state\n"); } /* Get controller data if one is supplied */ chip_info = spi->controller_data; if (chip_info == NULL) { if (np) { chip_info_dt = pl022_default_chip_info; chip_info_dt.hierarchy = SSP_MASTER; of_property_read_u32(np, "pl022,interface", &chip_info_dt.iface); of_property_read_u32(np, "pl022,com-mode", &chip_info_dt.com_mode); of_property_read_u32(np, "pl022,rx-level-trig", &chip_info_dt.rx_lev_trig); of_property_read_u32(np, "pl022,tx-level-trig", &chip_info_dt.tx_lev_trig); of_property_read_u32(np, "pl022,ctrl-len", &chip_info_dt.ctrl_len); of_property_read_u32(np, "pl022,wait-state", &chip_info_dt.wait_state); of_property_read_u32(np, "pl022,duplex", &chip_info_dt.duplex); chip_info = &chip_info_dt; } else { chip_info = &pl022_default_chip_info; /* spi_board_info.controller_data not is supplied */ dev_dbg(&spi->dev, "using default controller_data settings\n"); } } else dev_dbg(&spi->dev, "using user supplied controller_data settings\n"); /* * We can override with custom divisors, else we use the board * frequency setting */ if ((0 == chip_info->clk_freq.cpsdvsr) && (0 == chip_info->clk_freq.scr)) { status = calculate_effective_freq(pl022, spi->max_speed_hz, &clk_freq); if (status < 0) goto err_config_params; } else { memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq)); if ((clk_freq.cpsdvsr % 2) != 0) clk_freq.cpsdvsr = clk_freq.cpsdvsr - 1; } if ((clk_freq.cpsdvsr < CPSDVR_MIN) || (clk_freq.cpsdvsr > CPSDVR_MAX)) { status = -EINVAL; dev_err(&spi->dev, "cpsdvsr is configured incorrectly\n"); goto err_config_params; } status = verify_controller_parameters(pl022, chip_info); if (status) { dev_err(&spi->dev, "controller data is incorrect"); goto err_config_params; } pl022->rx_lev_trig = chip_info->rx_lev_trig; pl022->tx_lev_trig = chip_info->tx_lev_trig; /* Now set controller state based on controller data */ chip->xfer_type = chip_info->com_mode; if (!chip_info->cs_control) { chip->cs_control = null_cs_control; if (!gpio_is_valid(pl022->chipselects[spi->chip_select])) dev_warn(&spi->dev, "invalid chip select\n"); } else chip->cs_control = chip_info->cs_control; /* Check bits per word with vendor specific range */ if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) { status = -ENOTSUPP; dev_err(&spi->dev, "illegal data size for this controller!\n"); dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n", pl022->vendor->max_bpw); goto err_config_params; } else if (bits <= 8) { dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n"); chip->n_bytes = 1; chip->read = READING_U8; chip->write = WRITING_U8; } else if (bits <= 16) { dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n"); chip->n_bytes = 2; chip->read = READING_U16; chip->write = WRITING_U16; } else { dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n"); chip->n_bytes = 4; chip->read = READING_U32; chip->write = WRITING_U32; } /* Now Initialize all register settings required for this chip */ chip->cr0 = 0; chip->cr1 = 0; chip->dmacr = 0; chip->cpsr = 0; if ((chip_info->com_mode == DMA_TRANSFER) && ((pl022->master_info)->enable_dma)) { chip->enable_dma = true; dev_dbg(&spi->dev, "DMA mode set in controller state\n"); SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED, SSP_DMACR_MASK_RXDMAE, 0); SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED, SSP_DMACR_MASK_TXDMAE, 1); } else { chip->enable_dma = false; dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n"); SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0); SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1); } chip->cpsr = clk_freq.cpsdvsr; /* Special setup for the ST micro extended control registers */ if (pl022->vendor->extended_cr) { u32 etx; if (pl022->vendor->pl023) { /* These bits are only in the PL023 */ SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay, SSP_CR1_MASK_FBCLKDEL_ST, 13); } else { /* These bits are in the PL022 but not PL023 */ SSP_WRITE_BITS(chip->cr0, chip_info->duplex, SSP_CR0_MASK_HALFDUP_ST, 5); SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len, SSP_CR0_MASK_CSS_ST, 16); SSP_WRITE_BITS(chip->cr0, chip_info->iface, SSP_CR0_MASK_FRF_ST, 21); SSP_WRITE_BITS(chip->cr1, chip_info->wait_state, SSP_CR1_MASK_MWAIT_ST, 6); } SSP_WRITE_BITS(chip->cr0, bits - 1, SSP_CR0_MASK_DSS_ST, 0); if (spi->mode & SPI_LSB_FIRST) { tmp = SSP_RX_LSB; etx = SSP_TX_LSB; } else { tmp = SSP_RX_MSB; etx = SSP_TX_MSB; } SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4); SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5); SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig, SSP_CR1_MASK_RXIFLSEL_ST, 7); SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig, SSP_CR1_MASK_TXIFLSEL_ST, 10); } else { SSP_WRITE_BITS(chip->cr0, bits - 1, SSP_CR0_MASK_DSS, 0); SSP_WRITE_BITS(chip->cr0, chip_info->iface, SSP_CR0_MASK_FRF, 4); } /* Stuff that is common for all versions */ if (spi->mode & SPI_CPOL) tmp = SSP_CLK_POL_IDLE_HIGH; else tmp = SSP_CLK_POL_IDLE_LOW; SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6); if (spi->mode & SPI_CPHA) tmp = SSP_CLK_SECOND_EDGE; else tmp = SSP_CLK_FIRST_EDGE; SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7); SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8); /* Loopback is available on all versions except PL023 */ if (pl022->vendor->loopback) { if (spi->mode & SPI_LOOP) tmp = LOOPBACK_ENABLED; else tmp = LOOPBACK_DISABLED; SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0); } SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1); SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2); SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD, 3); /* Save controller_state */ spi_set_ctldata(spi, chip); return status; err_config_params: spi_set_ctldata(spi, NULL); kfree(chip); return status; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij91873.68%642.86%
roland stiggeroland stigge13911.16%214.29%
kevin wellskevin wells13210.59%17.14%
vinit shenoyvinit shenoy393.13%17.14%
jonas abergjonas aberg90.72%17.14%
virupax sadashivpetimathvirupax sadashivpetimath50.40%17.14%
viresh kumarviresh kumar30.24%17.14%
philippe langlaisphilippe langlais10.08%17.14%
Total1246100.00%14100.00%

/** * pl022_cleanup - cleanup function registered to SPI master framework * @spi: spi device which is requesting cleanup * * This function is registered to the SPI framework for this SPI master * controller. It will free the runtime state of chip. */
static void pl022_cleanup(struct spi_device *spi) { struct chip_data *chip = spi_get_ctldata(spi); spi_set_ctldata(spi, NULL); kfree(chip); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij33100.00%1100.00%
Total33100.00%1100.00%


static struct pl022_ssp_controller * pl022_platform_data_dt_get(struct device *dev) { struct device_node *np = dev->of_node; struct pl022_ssp_controller *pd; u32 tmp; if (!np) { dev_err(dev, "no dt node defined\n"); return NULL; } pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL); if (!pd) return NULL; pd->bus_id = -1; pd->enable_dma = 1; of_property_read_u32(np, "num-cs", &tmp); pd->num_chipselect = tmp; of_property_read_u32(np, "pl022,autosuspend-delay", &pd->autosuspend_delay); pd->rt = of_property_read_bool(np, "pl022,rt"); return pd; }

Contributors

PersonTokensPropCommitsCommitProp
roland stiggeroland stigge11894.40%133.33%
linus walleijlinus walleij75.60%266.67%
Total125100.00%3100.00%


static int pl022_probe(struct amba_device *adev, const struct amba_id *id) { struct device *dev = &adev->dev; struct pl022_ssp_controller *platform_info = dev_get_platdata(&adev->dev); struct spi_master *master; struct pl022 *pl022 = NULL; /*Data for this driver */ struct device_node *np = adev->dev.of_node; int status = 0, i, num_cs; dev_info(&adev->dev, "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid); if (!platform_info && IS_ENABLED(CONFIG_OF)) platform_info = pl022_platform_data_dt_get(dev); if (!platform_info) { dev_err(dev, "probe: no platform data defined\n"); return -ENODEV; } if (platform_info->num_chipselect) { num_cs = platform_info->num_chipselect; } else { dev_err(dev, "probe: no chip select defined\n"); return -ENODEV; } /* Allocate master with space for data */ master = spi_alloc_master(dev, sizeof(struct pl022)); if (master == NULL) { dev_err(&adev->dev, "probe - cannot alloc SPI master\n"); return -ENOMEM; } pl022 = spi_master_get_devdata(master); pl022->master = master; pl022->master_info = platform_info; pl022->adev = adev; pl022->vendor = id->data; pl022->chipselects = devm_kzalloc(dev, num_cs * sizeof(int), GFP_KERNEL); if (!pl022->chipselects) { status = -ENOMEM; goto err_no_mem; } /* * Bus Number Which has been Assigned to this SSP controller * on this board */ master->bus_num = platform_info->bus_id; master->num_chipselect = num_cs; master->cleanup = pl022_cleanup; master->setup = pl022_setup; master->auto_runtime_pm = true; master->transfer_one_message = pl022_transfer_one_message; master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware; master->rt = platform_info->rt; master->dev.of_node = dev->of_node; if (platform_info->num_chipselect && platform_info->chipselects) { for (i = 0; i < num_cs; i++) pl022->chipselects[i] = platform_info->chipselects[i]; } else if (pl022->vendor->internal_cs_ctrl) { for (i = 0; i < num_cs; i++) pl022->chipselects[i] = i; } else if (IS_ENABLED(CONFIG_OF)) { for (i = 0; i < num_cs; i++) { int cs_gpio = of_get_named_gpio(np, "cs-gpios", i); if (cs_gpio == -EPROBE_DEFER) { status = -EPROBE_DEFER; goto err_no_gpio; } pl022->chipselects[i] = cs_gpio; if (gpio_is_valid(cs_gpio)) { if (devm_gpio_request(dev, cs_gpio, "ssp-pl022")) dev_err(&adev->dev, "could not request %d gpio\n", cs_gpio); else if (gpio_direction_output(cs_gpio, 1)) dev_err(&adev->dev, "could not set gpio %d as output\n", cs_gpio); } } } /* * Supports mode 0-3, loopback, and active low CS. Transfers are * always MS bit first on the original pl022. */ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP; if (pl022->vendor->extended_cr) master->mode_bits |= SPI_LSB_FIRST; dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num); status = amba_request_regions(adev, NULL); if (status) goto err_no_ioregion; pl022->phybase = adev->res.start; pl022->virtbase = devm_ioremap(dev, adev->res.start, resource_size(&adev->res)); if (pl022->virtbase == NULL) { status = -ENOMEM; goto err_no_ioremap; } dev_info(&adev->dev, "mapped registers from %pa to %p\n", &adev->res.start, pl022->virtbase); pl022->clk = devm_clk_get(&adev->dev, NULL); if (IS_ERR(pl022->clk)) { status = PTR_ERR(pl022->clk); dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n"); goto err_no_clk; } status = clk_prepare_enable(pl022->clk); if (status) { dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n"); goto err_no_clk_en; } /* Initialize transfer pump */ tasklet_init(&pl022->pump_transfers, pump_transfers, (unsigned long)pl022); /* Disable SSP */ writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase)); load_ssp_default_config(pl022); status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler, 0, "pl022", pl022); if (status < 0) { dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status); goto err_no_irq; } /* Get DMA channels, try autoconfiguration first */ status = pl022_dma_autoprobe(pl022); if (status == -EPROBE_DEFER) { dev_dbg(dev, "deferring probe to get DMA channel\n"); goto err_no_irq; } /* If that failed, use channels from platform_info */ if (status == 0) platform_info->enable_dma = 1; else if (platform_info->enable_dma) { status = pl022_dma_probe(pl022); if (status != 0) platform_info->enable_dma = 0; } /* Register with the SPI framework */ amba_set_drvdata(adev, pl022); status = devm_spi_register_master(&adev->dev, master); if (status != 0) { dev_err(&adev->dev, "probe - problem registering spi master\n"); goto err_spi_register; } dev_dbg(dev, "probe succeeded\n"); /* let runtime pm put suspend */ if (platform_info->autosuspend_delay > 0) { dev_info(&adev->dev, "will use autosuspend for runtime pm, delay %dms\n", platform_info->autosuspend_delay); pm_runtime_set_autosuspend_delay(dev, platform_info->autosuspend_delay); pm_runtime_use_autosuspend(dev); } pm_runtime_put(dev); return 0; err_spi_register: if (platform_info->enable_dma) pl022_dma_remove(pl022); err_no_irq: clk_disable_unprepare(pl022->clk); err_no_clk_en: err_no_clk: err_no_ioremap: amba_release_regions(adev); err_no_ioregion: err_no_gpio: err_no_mem: spi_master_put(master); return status; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij53853.00%517.24%
roland stiggeroland stigge24524.14%517.24%
chris blairchris blair383.74%13.45%
ulf hanssonulf hansson353.45%26.90%
anders berganders berg333.25%13.45%
kevin wellskevin wells272.66%13.45%
arnd bergmannarnd bergmann222.17%13.45%
rabin vincentrabin vincent191.87%13.45%
kiran padwalkiran padwal191.87%13.45%
jingoo hanjingoo han171.67%310.34%
viresh kumarviresh kumar121.18%26.90%
russell kingrussell king60.59%310.34%
mark brownmark brown20.20%13.45%
fabio estevamfabio estevam10.10%13.45%
lucas de marchilucas de marchi10.10%13.45%
Total1015100.00%29100.00%


static int pl022_remove(struct amba_device *adev) { struct pl022 *pl022 = amba_get_drvdata(adev); if (!pl022) return 0; /* * undo pm_runtime_put() in probe. I assume that we're not * accessing the primecell here. */ pm_runtime_get_noresume(&adev->dev); load_ssp_default_config(pl022); if (pl022->master_info->enable_dma) pl022_dma_remove(pl022); clk_disable_unprepare(pl022->clk); amba_release_regions(adev); tasklet_disable(&pl022->pump_transfers); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij5569.62%233.33%
russell kingrussell king1518.99%233.33%
viresh kumarviresh kumar810.13%116.67%
ulf hanssonulf hansson11.27%116.67%
Total79100.00%6100.00%

#ifdef CONFIG_PM_SLEEP
static int pl022_suspend(struct device *dev) { struct pl022 *pl022 = dev_get_drvdata(dev); int ret; ret = spi_master_suspend(pl022->master); if (ret) { dev_warn(dev, "cannot suspend master\n"); return ret; } ret = pm_runtime_force_suspend(dev); if (ret) { spi_master_resume(pl022->master); return ret; } pinctrl_pm_select_sleep_state(dev); dev_dbg(dev, "suspended\n"); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij5866.67%342.86%
ulf hanssonulf hansson2427.59%228.57%
russell kingrussell king44.60%114.29%
peter huewepeter huewe11.15%114.29%
Total87100.00%7100.00%


static int pl022_resume(struct device *dev) { struct pl022 *pl022 = dev_get_drvdata(dev); int ret; ret = pm_runtime_force_resume(dev); if (ret) dev_err(dev, "problem resuming\n"); /* Start the queue running */ ret = spi_master_resume(pl022->master); if (ret) dev_err(dev, "problem starting queue (%d)\n", ret); else dev_dbg(dev, "resumed\n"); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij5977.63%350.00%
ulf hanssonulf hansson1317.11%233.33%
russell kingrussell king45.26%116.67%
Total76100.00%6100.00%

#endif #ifdef CONFIG_PM
static int pl022_runtime_suspend(struct device *dev) { struct pl022 *pl022 = dev_get_drvdata(dev); clk_disable_unprepare(pl022->clk); pinctrl_pm_select_idle_state(dev); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
russell kingrussell king2877.78%150.00%
ulf hanssonulf hansson822.22%150.00%
Total36100.00%2100.00%


static int pl022_runtime_resume(struct device *dev) { struct pl022 *pl022 = dev_get_drvdata(dev); pinctrl_pm_select_default_state(dev); clk_prepare_enable(pl022->clk); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
russell kingrussell king2672.22%133.33%
ulf hanssonulf hansson822.22%133.33%
patrice chotardpatrice chotard25.56%133.33%
Total36100.00%3100.00%

#endif static const struct dev_pm_ops pl022_dev_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume) SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL) }; static struct vendor_data vendor_arm = { .fifodepth = 8, .max_bpw = 16, .unidir = false, .extended_cr = false, .pl023 = false, .loopback = true, .internal_cs_ctrl = false, }; static struct vendor_data vendor_st = { .fifodepth = 32, .max_bpw = 32, .unidir = false, .extended_cr = true, .pl023 = false, .loopback = true, .internal_cs_ctrl = false, }; static struct vendor_data vendor_st_pl023 = { .fifodepth = 32, .max_bpw = 32, .unidir = false, .extended_cr = true, .pl023 = true, .loopback = false, .internal_cs_ctrl = false, }; static struct vendor_data vendor_lsi = { .fifodepth = 8, .max_bpw = 16, .unidir = false, .extended_cr = false, .pl023 = false, .loopback = true, .internal_cs_ctrl = true, }; static struct amba_id pl022_ids[] = { { /* * ARM PL022 variant, this has a 16bit wide * and 8 locations deep TX/RX FIFO */ .id = 0x00041022, .mask = 0x000fffff, .data = &vendor_arm, }, { /* * ST Micro derivative, this has 32bit wide * and 32 locations deep TX/RX FIFO */ .id = 0x01080022, .mask = 0xffffffff, .data = &vendor_st, }, { /* * ST-Ericsson derivative "PL023" (this is not * an official ARM number), this is a PL022 SSP block * stripped to SPI mode only, it has 32bit wide * and 32 locations deep TX/RX FIFO but no extended * CR0/CR1 register */ .id = 0x00080023, .mask = 0xffffffff, .data = &vendor_st_pl023, }, { /* * PL022 variant that has a chip select control register whih * allows control of 5 output signals nCS[0:4]. */ .id = 0x000b6022, .mask = 0x000fffff, .data = &vendor_lsi, }, { 0, 0 }, }; MODULE_DEVICE_TABLE(amba, pl022_ids); static struct amba_driver pl022_driver = { .drv = { .name = "ssp-pl022", .pm = &pl022_dev_pm_ops, }, .id_table = pl022_ids, .probe = pl022_probe, .remove = pl022_remove, };
static int __init pl022_init(void) { return amba_driver_register(&pl022_driver); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij16100.00%1100.00%
Total16100.00%1100.00%

subsys_initcall(pl022_init);
static void __exit pl022_exit(void) { amba_driver_unregister(&pl022_driver); }

Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij15100.00%1100.00%
Total15100.00%1100.00%

module_exit(pl022_exit); MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>"); MODULE_DESCRIPTION("PL022 SSP Controller Driver"); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
linus walleijlinus walleij756479.05%2025.00%
roland stiggeroland stigge5966.23%56.25%
viresh kumarviresh kumar2252.35%911.25%
anders berganders berg2102.19%11.25%
kevin wellskevin wells1591.66%11.25%
arnd bergmannarnd bergmann1471.54%11.25%
russell kingrussell king1151.20%33.75%
virupax sadashivpetimathvirupax sadashivpetimath981.02%45.00%
ulf hanssonulf hansson910.95%56.25%
rabin vincentrabin vincent780.82%22.50%
chris blairchris blair680.71%33.75%
magnus templingmagnus templing610.64%11.25%
vinit shenoyvinit shenoy390.41%11.25%
philippe langlaisphilippe langlais210.22%11.25%
kiran padwalkiran padwal190.20%11.25%
jingoo hanjingoo han170.18%33.75%
jonas abergjonas aberg90.09%11.25%
alexander sverdlinalexander sverdlin80.08%22.50%
mark brownmark brown70.07%22.50%
dave martindave martin70.07%11.25%
lucas de marchilucas de marchi60.06%11.25%
patrice chotardpatrice chotard50.05%11.25%
vinod koulvinod koul40.04%11.25%
tejun heotejun heo30.03%11.25%
axel linaxel lin20.02%11.25%
alexandre bouninealexandre bounine20.02%11.25%
julia lawalljulia lawall20.02%11.25%
ray juiray jui10.01%11.25%
fabio estevamfabio estevam10.01%11.25%
srinidhi kasagarsrinidhi kasagar10.01%11.25%
rafael j. wysockirafael j. wysocki10.01%11.25%
jarkko nikulajarkko nikula10.01%11.25%
peter huewepeter huewe10.01%11.25%
grant likelygrant likely0.00%00.00%
Total9569100.00%80100.00%
Directory: drivers/spi
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.