Hi Wolfram,
On Wed, 06 Feb 2008 21:20:59 +0100, Wolfram Sang wrote:
> Tested on a blackfin.
>
> Signed-off-by: Wolfram Sang <[EMAIL PROTECTED]>
>
> ---
> drivers/i2c/busses/Kconfig | 11 +
> drivers/i2c/busses/Makefile | 1
> drivers/i2c/busses/i2c-pca-platform.c | 278
> ++++++++++++++++++++++++++++++++++
> include/linux/i2c-pca-platform.h | 12 +
> 4 files changed, 302 insertions(+)
>
> Index: linux-playground/drivers/i2c/busses/i2c-pca-platform.c
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux-playground/drivers/i2c/busses/i2c-pca-platform.c 2008-02-06
> 20:15:54.000000000 +0100
> @@ -0,0 +1,278 @@
> +/*
> + * i2c_pca_platform.c
> + *
> + * Platform driver for the PCA9564 I2C controller.
> + *
> + * Copyright (C) 2008 Pengutronix
> + *
> + * 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.
> + *
> + */
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/slab.h>
> +#include <linux/delay.h>
> +#include <linux/errno.h>
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>
> +#include <linux/platform_device.h>
> +#include <linux/i2c-algo-pca.h>
> +#include <linux/i2c-pca-platform.h>
> +
> +#include <asm/irq.h>
> +#include <asm/io.h>
> +
> +#ifdef GENERIC_GPIO
> +#include <asm/gpio.h>
> +#endif
> +
> +#define res_len(r) ((r)->end - (r)->start + 1)
> +
> +struct i2c_pca_pf_data {
> + void __iomem *reg_base;
> + int irq; /* if 0, use polling */
> + wait_queue_head_t wait;
> + struct i2c_adapter adap;
> + struct i2c_algo_pca_data algo_data;
> + unsigned long io_base;
> + unsigned long io_size;
> +};
> +
> +/* Read/Write functions for different register alignments */
> +
> +static int i2c_pca_pf_readbyte8(void *pd, int reg)
> +{
> + struct i2c_pca_pf_data *i2c = pd;
> + return ioread8(i2c->reg_base + reg);
> +}
> +
> +static int i2c_pca_pf_readbyte16(void *pd, int reg)
> +{
> + struct i2c_pca_pf_data *i2c = pd;
> + return ioread8(i2c->reg_base + reg * 2);
Shouldn't this be ioread16?
> +}
> +
> +static int i2c_pca_pf_readbyte32(void *pd, int reg)
> +{
> + struct i2c_pca_pf_data *i2c = pd;
> + return ioread8(i2c->reg_base + reg * 4);
> +}
And ioread32?
> +
> +static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
> +{
> + struct i2c_pca_pf_data *i2c = pd;
> + iowrite8(val, i2c->reg_base + reg);
> +}
> +
> +static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
> +{
> + struct i2c_pca_pf_data *i2c = pd;
> + iowrite8(val, i2c->reg_base + reg * 2);
> +}
> +
> +static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
> +{
> + struct i2c_pca_pf_data *i2c = pd;
> + iowrite8(val, i2c->reg_base + reg * 4);
> +}
> +
> +
> +static int i2c_pca_pf_waitforcompletion(void *pd)
> +{
> + struct i2c_pca_pf_data *i2c = pd;
> + int ret = 0;
> +
> + if (i2c->irq) {
> + ret = wait_event_interruptible(i2c->wait,
> + i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
> + & I2C_PCA_CON_SI);
> + } else {
> + while ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
> + & I2C_PCA_CON_SI) == 0)
> + udelay(100);
No timeout?
> + }
> +
> + return ret;
> +}
> +
> +static void i2c_pca_pf_dummyreset(void *pd)
> +{
> + struct i2c_pca_pf_data *i2c = pd;
> + dev_warn(&i2c->adap.dev, "No reset-pin found. Chip may get stuck!\n");
> +}
> +
> +#ifdef GENERIC_GPIO
> +static void i2c_pca_pf_resetchip(void *pd)
> +{
> + struct i2c_pca_pf_data *i2c = pd;
> + struct i2c_pca9564_pf_platform_data *platform_data =
> + i2c->adap.dev.parent->platform_data;
> +
> + gpio_set_value(platform_data->gpio, 0);
The i2c_clock gets to be copied to the driver data structure, but for
the gpio you have to fetch it from the platform device data? Not very
consistent.
> + ndelay(100);
> + gpio_set_value(platform_data->gpio, 1);
> +}
> +#endif
> +
> +static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
> +{
> + struct i2c_pca_pf_data *i2c = dev_id;
> +
> + if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
> + return IRQ_NONE;
> +
> + wake_up_interruptible(&i2c->wait);
> +
> + return IRQ_HANDLED;
> +}
> +
> +
> +static int i2c_pca_pf_probe(struct platform_device *pdev)
> +{
> + struct i2c_pca_pf_data *i2c;
> + struct resource *res;
> + struct i2c_pca9564_pf_platform_data *platform_data =
> + pdev->dev.platform_data;
> + int ret;
> + int irq;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + irq = platform_get_irq(pdev, 0);
> + /* If irq is 0, we do polling. */
> +
> + if (res == NULL)
> + return -ENODEV;
> +
> + if (!request_mem_region(res->start, res_len(res), res->name))
> + return -ENOMEM;
> +
> + i2c = kzalloc(sizeof(struct i2c_pca_pf_data), GFP_KERNEL);
> + if (!i2c) {
> + ret = -ENOMEM;
> + goto e_alloc;
> + }
> +
> + init_waitqueue_head(&i2c->wait);
> +
> + i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
> +
> + i2c->adap.owner = THIS_MODULE;
No alignment in code please.
> + snprintf(i2c->adap.name, sizeof(i2c->adap.name), "i2c-pca9564.%u",
> + pdev->id);
That's a bit confusing given that the driver isn't named i2c-pca9564.
Other drivers usually include the address to distinguish between
multiple device for example (..., "PCA9564 adapter at %04lx",
res->start).
> + i2c->adap.algo_data = &i2c->algo_data;
> + i2c->adap.dev.parent = &pdev->dev;
> + i2c->adap.timeout = platform_data->timeout;
> +
> + i2c->reg_base = ioremap(res->start, res_len(res));
> + if (!i2c->reg_base) {
> + ret = -EIO;
> + goto e_remap;
> + }
> + i2c->io_base = res->start;
> + i2c->io_size = res_len(res);
> + i2c->irq = irq;
> +
> + i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
> + i2c->algo_data.data = i2c;
> +
> + switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
> + case IORESOURCE_MEM_32BIT:
> + i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
> + i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
> + break;
> + case IORESOURCE_MEM_16BIT:
> + i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
> + i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
> + break;
> + case IORESOURCE_MEM_8BIT:
> + default:
> + i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
> + i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
> + break;
> + }
> +
> + i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
> +
> +#ifdef GENERIC_GPIO
> + /* Use NO_GPIO if this macro is in kernel somwhen? */
No "somwhen" in my dictionary.
> + if (platform_data->gpio > -1)
> + i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
> + else
> + i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
> +#else
> + i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
> +#endif
> + if (irq) {
> + ret = request_irq(irq, i2c_pca_pf_handler,
> + IRQF_TRIGGER_FALLING, i2c->adap.name, i2c);
> + if (ret)
> + goto e_reqirq;
> + }
> +
> + if (i2c_pca_add_numbered_bus(&i2c->adap) < 0) {
> + dev_err(&i2c->adap.dev, "Failed to add PCA9564\n");
> + goto e_adapt;
> + }
> +
> + platform_set_drvdata(pdev, i2c);
> +
> + dev_info(&i2c->adap.dev, "PCA9564 registered.\n");
> + return 0;
> +
> +e_adapt:
> + if (irq)
> + free_irq(irq, i2c);
> +e_reqirq:
> + iounmap(i2c->reg_base);
> +e_remap:
> + kfree(i2c);
> +e_alloc:
> + release_mem_region(res->start, res_len(res));
> + return ret;
> +}
> +
> +static int i2c_pca_pf_remove(struct platform_device *pdev)
Missing __devexit.
> +{
> + struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
> + platform_set_drvdata(pdev, NULL);
> +
> + i2c_del_adapter(&i2c->adap);
> +
> + if (i2c->irq)
> + free_irq(i2c->irq, i2c);
> +
> + iounmap(i2c->reg_base);
> + release_mem_region(i2c->io_base, i2c->io_size);
> + kfree(i2c);
> +
> + return 0;
> +}
> +
> +static struct platform_driver i2c_pca_pf_driver = {
> + .probe = i2c_pca_pf_probe,
> + .remove = __devexit_p(i2c_pca_pf_remove),
> + .driver = {
> + .name = "pca9564_platform",
Missing .owner = THIS_MODULE.
> + },
> +};
> +
> +static int __init i2c_pca_pf_init(void)
> +{
> + return platform_driver_register(&i2c_pca_pf_driver);
> +}
> +
> +static void __exit i2c_pca_pf_exit(void)
> +{
> + platform_driver_unregister(&i2c_pca_pf_driver);
> +}
> +
> +MODULE_AUTHOR("Wolfram Sang <[EMAIL PROTECTED]>");
> +MODULE_DESCRIPTION("I2C-PCA9564 platform driver");
> +MODULE_LICENSE("GPL");
> +
> +module_init(i2c_pca_pf_init);
> +module_exit(i2c_pca_pf_exit);
> +
> Index: linux-playground/drivers/i2c/busses/Kconfig
> ===================================================================
> --- linux-playground.orig/drivers/i2c/busses/Kconfig 2008-02-06
> 20:15:36.000000000 +0100
> +++ linux-playground/drivers/i2c/busses/Kconfig 2008-02-06
> 20:15:54.000000000 +0100
> @@ -641,6 +641,17 @@
> delays when I2C/SMBus chip drivers are loaded (e.g. at boot
> time). If unsure, say N.
>
> +config I2C_PCA_PLATFORM
> + tristate "PCA9564 as platform device"
> + select I2C_ALGOPCA
> + default n
> + help
> + This driver supports a memory mapped Philips PCA 9564
For consistency, no space between "PCA" and "9564".
> + Parallel bus to I2C bus controller
Lowercase P, missing trailing dot.
> +
> + This driver can also be built as a module. If so, the module
> + will be called i2c-pca-platform.
> +
> config I2C_MV64XXX
> tristate "Marvell mv64xxx I2C Controller"
> depends on (MV64X60 || ARCH_ORION) && EXPERIMENTAL
> Index: linux-playground/drivers/i2c/busses/Makefile
> ===================================================================
> --- linux-playground.orig/drivers/i2c/busses/Makefile 2008-02-06
> 20:15:36.000000000 +0100
> +++ linux-playground/drivers/i2c/busses/Makefile 2008-02-06
> 20:15:55.000000000 +0100
> @@ -30,6 +30,7 @@
> obj-$(CONFIG_I2C_PARPORT_LIGHT) += i2c-parport-light.o
> obj-$(CONFIG_I2C_PASEMI) += i2c-pasemi.o
> obj-$(CONFIG_I2C_PCA_ISA) += i2c-pca-isa.o
> +obj-$(CONFIG_I2C_PCA_PLATFORM) += i2c-pca-platform.o
> obj-$(CONFIG_I2C_PIIX4) += i2c-piix4.o
> obj-$(CONFIG_I2C_PMCMSP) += i2c-pmcmsp.o
> obj-$(CONFIG_I2C_PNX) += i2c-pnx.o
> Index: linux-playground/include/linux/i2c-pca-platform.h
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux-playground/include/linux/i2c-pca-platform.h 2008-02-06
> 20:15:55.000000000 +0100
> @@ -0,0 +1,12 @@
> +#ifndef I2C_PCA9564_PLATFORM_H
> +#define I2C_PCA9564_PLATFORM_H
> +
> +struct i2c_pca9564_pf_platform_data {
"pf" is redundant with "platform", isn't it?
> + int gpio; /* pin to reset chip. driver will work when
> + * not supplied (negative value), but it
> + * cannot exit some error conditions then */
> + int i2c_clock_speed; /* values are defined in linux/i2c-algo-pca.h */
> + int timeout; /* timeout = this value * 10us */
A rather curious time unit if you ask me.
> +};
> +
> +#endif /* I2C_PCA9564_PLATFORM_H */
>
--
Jean Delvare
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