cregit-Linux how code gets into the kernel

Release 4.7 drivers/media/usb/go7007/go7007-i2c.c

/*
 * Copyright (C) 2005-2006 Micronas USA Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License (Version 2) as
 * published by the Free Software Foundation.
 *
 * 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/module.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/list.h>
#include <linux/unistd.h>
#include <linux/time.h>
#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/uaccess.h>

#include "go7007-priv.h"

/********************* Driver for on-board I2C adapter *********************/

/* #define GO7007_I2C_DEBUG */


#define SPI_I2C_ADDR_BASE		0x1400

#define STATUS_REG_ADDR			(SPI_I2C_ADDR_BASE + 0x2)

#define I2C_CTRL_REG_ADDR		(SPI_I2C_ADDR_BASE + 0x6)

#define I2C_DEV_UP_ADDR_REG_ADDR	(SPI_I2C_ADDR_BASE + 0x7)

#define I2C_LO_ADDR_REG_ADDR		(SPI_I2C_ADDR_BASE + 0x8)

#define I2C_DATA_REG_ADDR		(SPI_I2C_ADDR_BASE + 0x9)

#define I2C_CLKFREQ_REG_ADDR		(SPI_I2C_ADDR_BASE + 0xa)


#define I2C_STATE_MASK			0x0007

#define I2C_READ_READY_MASK		0x0008

/* There is only one I2C port on the TW2804 that feeds all four GO7007 VIPs
 * on the Adlink PCI-MPG24, so access is shared between all of them. */
static DEFINE_MUTEX(adlink_mpg24_i2c_lock);


static int go7007_i2c_xfer(struct go7007 *go, u16 addr, int read, u16 command, int flags, u8 *data) { int i, ret = -EIO; u16 val; if (go->status == STATUS_SHUTDOWN) return -ENODEV; #ifdef GO7007_I2C_DEBUG if (read) dev_dbg(go->dev, "go7007-i2c: reading 0x%02x on 0x%02x\n", command, addr); else dev_dbg(go->dev, "go7007-i2c: writing 0x%02x to 0x%02x on 0x%02x\n", *data, command, addr); #endif mutex_lock(&go->hw_lock); if (go->board_id == GO7007_BOARDID_ADLINK_MPG24) { /* Bridge the I2C port on this GO7007 to the shared bus */ mutex_lock(&adlink_mpg24_i2c_lock); go7007_write_addr(go, 0x3c82, 0x0020); } /* Wait for I2C adapter to be ready */ for (i = 0; i < 10; ++i) { if (go7007_read_addr(go, STATUS_REG_ADDR, &val) < 0) goto i2c_done; if (!(val & I2C_STATE_MASK)) break; msleep(100); } if (i == 10) { dev_err(go->dev, "go7007-i2c: I2C adapter is hung\n"); goto i2c_done; } /* Set target register (command) */ go7007_write_addr(go, I2C_CTRL_REG_ADDR, flags); go7007_write_addr(go, I2C_LO_ADDR_REG_ADDR, command); /* If we're writing, send the data and target address and we're done */ if (!read) { go7007_write_addr(go, I2C_DATA_REG_ADDR, *data); go7007_write_addr(go, I2C_DEV_UP_ADDR_REG_ADDR, (addr << 9) | (command >> 8)); ret = 0; goto i2c_done; } /* Otherwise, we're reading. First clear i2c_rx_data_rdy. */ if (go7007_read_addr(go, I2C_DATA_REG_ADDR, &val) < 0) goto i2c_done; /* Send the target address plus read flag */ go7007_write_addr(go, I2C_DEV_UP_ADDR_REG_ADDR, (addr << 9) | 0x0100 | (command >> 8)); /* Wait for i2c_rx_data_rdy */ for (i = 0; i < 10; ++i) { if (go7007_read_addr(go, STATUS_REG_ADDR, &val) < 0) goto i2c_done; if (val & I2C_READ_READY_MASK) break; msleep(100); } if (i == 10) { dev_err(go->dev, "go7007-i2c: I2C adapter is hung\n"); goto i2c_done; } /* Retrieve the read byte */ if (go7007_read_addr(go, I2C_DATA_REG_ADDR, &val) < 0) goto i2c_done; *data = val; ret = 0; i2c_done: if (go->board_id == GO7007_BOARDID_ADLINK_MPG24) { /* Isolate the I2C port on this GO7007 from the shared bus */ go7007_write_addr(go, 0x3c82, 0x0000); mutex_unlock(&adlink_mpg24_i2c_lock); } mutex_unlock(&go->hw_lock); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
greg kroah-hartmangreg kroah-hartman39993.88%125.00%
toshiaki yamanetoshiaki yamane204.71%125.00%
mauro carvalho chehabmauro carvalho chehab40.94%125.00%
hans verkuilhans verkuil20.47%125.00%
Total425100.00%4100.00%


static int go7007_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, char read_write, u8 command, int size, union i2c_smbus_data *data) { struct go7007 *go = i2c_get_adapdata(adapter); if (size != I2C_SMBUS_BYTE_DATA) return -EIO; return go7007_i2c_xfer(go, addr, read_write == I2C_SMBUS_READ, command, flags & I2C_CLIENT_SCCB ? 0x10 : 0x00, &data->byte); }

Contributors

PersonTokensPropCommitsCommitProp
greg kroah-hartmangreg kroah-hartman7898.73%150.00%
hans verkuilhans verkuil11.27%150.00%
Total79100.00%2100.00%

/* VERY LIMITED I2C master xfer function -- only needed because the * SMBus functions only support 8-bit commands and the SAA7135 uses * 16-bit commands. The I2C interface on the GO7007, as limited as * it is, does support this mode. */
static int go7007_i2c_master_xfer(struct i2c_adapter *adapter, struct i2c_msg msgs[], int num) { struct go7007 *go = i2c_get_adapdata(adapter); int i; for (i = 0; i < num; ++i) { /* We can only do two things here -- write three bytes, or * write two bytes and read one byte. */ if (msgs[i].len == 2) { if (i + 1 == num || msgs[i].addr != msgs[i + 1].addr || (msgs[i].flags & I2C_M_RD) || !(msgs[i + 1].flags & I2C_M_RD) || msgs[i + 1].len != 1) return -EIO; if (go7007_i2c_xfer(go, msgs[i].addr, 1, (msgs[i].buf[0] << 8) | msgs[i].buf[1], 0x01, &msgs[i + 1].buf[0]) < 0) return -EIO; ++i; } else if (msgs[i].len == 3) { if (msgs[i].flags & I2C_M_RD) return -EIO; if (msgs[i].len != 3) return -EIO; if (go7007_i2c_xfer(go, msgs[i].addr, 0, (msgs[i].buf[0] << 8) | msgs[i].buf[1], 0x01, &msgs[i].buf[2]) < 0) return -EIO; } else return -EIO; } return num; }

Contributors

PersonTokensPropCommitsCommitProp
greg kroah-hartmangreg kroah-hartman29397.67%150.00%
hans verkuilhans verkuil72.33%150.00%
Total300100.00%2100.00%


static u32 go7007_functionality(struct i2c_adapter *adapter) { return I2C_FUNC_SMBUS_BYTE_DATA; }

Contributors

PersonTokensPropCommitsCommitProp
greg kroah-hartmangreg kroah-hartman14100.00%1100.00%
Total14100.00%1100.00%

static struct i2c_algorithm go7007_algo = { .smbus_xfer = go7007_smbus_xfer, .master_xfer = go7007_i2c_master_xfer, .functionality = go7007_functionality, }; static struct i2c_adapter go7007_adap_templ = { .owner = THIS_MODULE, .name = "WIS GO7007SB", .algo = &go7007_algo, };
int go7007_i2c_init(struct go7007 *go) { memcpy(&go->i2c_adapter, &go7007_adap_templ, sizeof(go7007_adap_templ)); go->i2c_adapter.dev.parent = go->dev; i2c_set_adapdata(&go->i2c_adapter, go); if (i2c_add_adapter(&go->i2c_adapter) < 0) { dev_err(go->dev, "go7007-i2c: error: i2c_add_adapter failed\n"); return -1; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
greg kroah-hartmangreg kroah-hartman7393.59%150.00%
toshiaki yamanetoshiaki yamane56.41%150.00%
Total78100.00%2100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
greg kroah-hartmangreg kroah-hartman97995.89%120.00%
toshiaki yamanetoshiaki yamane252.45%120.00%
hans verkuilhans verkuil111.08%240.00%
mauro carvalho chehabmauro carvalho chehab60.59%120.00%
Total1021100.00%5100.00%
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