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Release 4.7 drivers/input/serio/apbps2.c

/*
 * Copyright (C) 2013 Aeroflex Gaisler
 *
 * This driver supports the APBPS2 PS/2 core available in the GRLIB
 * VHDL IP core library.
 *
 * Full documentation of the APBPS2 core can be found here:
 * http://www.gaisler.com/products/grlib/grip.pdf
 *
 * See "Documentation/devicetree/bindings/input/ps2keyb-mouse-apbps2.txt" for
 * information on open firmware properties.
 *
 * 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.
 *
 * Contributors: Daniel Hellstrom <daniel@gaisler.com>
 */
#include <linux/platform_device.h>
#include <linux/of_device.h>
#include <linux/module.h>
#include <linux/serio.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/of_irq.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/io.h>


struct apbps2_regs {
	
u32 __iomem data;	/* 0x00 */
	
u32 __iomem status;	/* 0x04 */
	
u32 __iomem ctrl;	/* 0x08 */
	
u32 __iomem reload;	/* 0x0c */
};


#define APBPS2_STATUS_DR	(1<<0)

#define APBPS2_STATUS_PE	(1<<1)

#define APBPS2_STATUS_FE	(1<<2)

#define APBPS2_STATUS_KI	(1<<3)

#define APBPS2_STATUS_RF	(1<<4)

#define APBPS2_STATUS_TF	(1<<5)

#define APBPS2_STATUS_TCNT	(0x1f<<22)

#define APBPS2_STATUS_RCNT	(0x1f<<27)


#define APBPS2_CTRL_RE		(1<<0)

#define APBPS2_CTRL_TE		(1<<1)

#define APBPS2_CTRL_RI		(1<<2)

#define APBPS2_CTRL_TI		(1<<3)


struct apbps2_priv {
	
struct serio		*io;
	
struct apbps2_regs	*regs;
};


static int apbps2_idx;


static irqreturn_t apbps2_isr(int irq, void *dev_id) { struct apbps2_priv *priv = dev_id; unsigned long status, data, rxflags; irqreturn_t ret = IRQ_NONE; while ((status = ioread32be(&priv->regs->status)) & APBPS2_STATUS_DR) { data = ioread32be(&priv->regs->data); rxflags = (status & APBPS2_STATUS_PE) ? SERIO_PARITY : 0; rxflags |= (status & APBPS2_STATUS_FE) ? SERIO_FRAME : 0; /* clear error bits? */ if (rxflags) iowrite32be(0, &priv->regs->status); serio_interrupt(priv->io, data, rxflags); ret = IRQ_HANDLED; } return ret; }

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daniel hellstromdaniel hellstrom124100.00%1100.00%
Total124100.00%1100.00%


static int apbps2_write(struct serio *io, unsigned char val) { struct apbps2_priv *priv = io->port_data; unsigned int tleft = 10000; /* timeout in 100ms */ /* delay until PS/2 controller has room for more chars */ while ((ioread32be(&priv->regs->status) & APBPS2_STATUS_TF) && tleft--) udelay(10); if ((ioread32be(&priv->regs->status) & APBPS2_STATUS_TF) == 0) { iowrite32be(val, &priv->regs->data); iowrite32be(APBPS2_CTRL_RE | APBPS2_CTRL_RI | APBPS2_CTRL_TE, &priv->regs->ctrl); return 0; } return -ETIMEDOUT; }

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daniel hellstromdaniel hellstrom111100.00%1100.00%
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static int apbps2_open(struct serio *io) { struct apbps2_priv *priv = io->port_data; int limit; unsigned long tmp; /* clear error flags */ iowrite32be(0, &priv->regs->status); /* Clear old data if available (unlikely) */ limit = 1024; while ((ioread32be(&priv->regs->status) & APBPS2_STATUS_DR) && --limit) tmp = ioread32be(&priv->regs->data); /* Enable reciever and it's interrupt */ iowrite32be(APBPS2_CTRL_RE | APBPS2_CTRL_RI, &priv->regs->ctrl); return 0; }

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daniel hellstromdaniel hellstrom94100.00%1100.00%
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static void apbps2_close(struct serio *io) { struct apbps2_priv *priv = io->port_data; /* stop interrupts at PS/2 HW level */ iowrite32be(0, &priv->regs->ctrl); }

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daniel hellstromdaniel hellstrom33100.00%1100.00%
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/* Initialize one APBPS2 PS/2 core */
static int apbps2_of_probe(struct platform_device *ofdev) { struct apbps2_priv *priv; int irq, err; u32 freq_hz; struct resource *res; priv = devm_kzalloc(&ofdev->dev, sizeof(*priv), GFP_KERNEL); if (!priv) { dev_err(&ofdev->dev, "memory allocation failed\n"); return -ENOMEM; } /* Find Device Address */ res = platform_get_resource(ofdev, IORESOURCE_MEM, 0); priv->regs = devm_ioremap_resource(&ofdev->dev, res); if (IS_ERR(priv->regs)) return PTR_ERR(priv->regs); /* Reset hardware, disable interrupt */ iowrite32be(0, &priv->regs->ctrl); /* IRQ */ irq = irq_of_parse_and_map(ofdev->dev.of_node, 0); err = devm_request_irq(&ofdev->dev, irq, apbps2_isr, IRQF_SHARED, "apbps2", priv); if (err) { dev_err(&ofdev->dev, "request IRQ%d failed\n", irq); return err; } /* Get core frequency */ if (of_property_read_u32(ofdev->dev.of_node, "freq", &freq_hz)) { dev_err(&ofdev->dev, "unable to get core frequency\n"); return -EINVAL; } /* Set reload register to core freq in kHz/10 */ iowrite32be(freq_hz / 10000, &priv->regs->reload); priv->io = kzalloc(sizeof(struct serio), GFP_KERNEL); if (!priv->io) return -ENOMEM; priv->io->id.type = SERIO_8042; priv->io->open = apbps2_open; priv->io->close = apbps2_close; priv->io->write = apbps2_write; priv->io->port_data = priv; strlcpy(priv->io->name, "APBPS2 PS/2", sizeof(priv->io->name)); snprintf(priv->io->phys, sizeof(priv->io->phys), "apbps2_%d", apbps2_idx++); dev_info(&ofdev->dev, "irq = %d, base = 0x%p\n", irq, priv->regs); serio_register_port(priv->io); platform_set_drvdata(ofdev, priv); return 0; }

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daniel hellstromdaniel hellstrom36397.84%150.00%
sachin kamatsachin kamat82.16%150.00%
Total371100.00%2100.00%


static int apbps2_of_remove(struct platform_device *of_dev) { struct apbps2_priv *priv = platform_get_drvdata(of_dev); serio_unregister_port(priv->io); return 0; }

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daniel hellstromdaniel hellstrom31100.00%1100.00%
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static const struct of_device_id apbps2_of_match[] = { { .name = "GAISLER_APBPS2", }, { .name = "01_060", }, {} }; MODULE_DEVICE_TABLE(of, apbps2_of_match); static struct platform_driver apbps2_of_driver = { .driver = { .name = "grlib-apbps2", .of_match_table = apbps2_of_match, }, .probe = apbps2_of_probe, .remove = apbps2_of_remove, }; module_platform_driver(apbps2_of_driver); MODULE_AUTHOR("Aeroflex Gaisler AB."); MODULE_DESCRIPTION("GRLIB APBPS2 PS/2 serial I/O"); MODULE_LICENSE("GPL");

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daniel hellstromdaniel hellstrom97599.09%133.33%
sachin kamatsachin kamat80.81%133.33%
jingoo hanjingoo han10.10%133.33%
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