From 6b65cd742823f78a6538491982159098ab5fcae1 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sun, 10 Dec 2006 21:21:32 +0100 Subject: [PATCH] i2c: New ARM Versatile/Realview bus driver Add support for the I2C bus found on the ARM Versatile and Realview platforms. The I2C bus has a RTC and optionally some EEPROMs attached. Signed-off-by: Russell King Signed-off-by: Jean Delvare --- arch/arm/mach-realview/core.c | 13 +++ arch/arm/mach-realview/core.h | 1 + arch/arm/mach-realview/realview_eb.c | 1 + arch/arm/mach-versatile/core.c | 14 +++ drivers/i2c/busses/Kconfig | 11 ++ drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-versatile.c | 153 +++++++++++++++++++++++++++ 7 files changed, 194 insertions(+) create mode 100644 drivers/i2c/busses/i2c-versatile.c diff --git a/arch/arm/mach-realview/core.c b/arch/arm/mach-realview/core.c index 68c67053f479..84d3fe76e94e 100644 --- a/arch/arm/mach-realview/core.c +++ b/arch/arm/mach-realview/core.c @@ -141,6 +141,19 @@ struct platform_device realview_smc91x_device = { .resource = realview_smc91x_resources, }; +static struct resource realview_i2c_resource = { + .start = REALVIEW_I2C_BASE, + .end = REALVIEW_I2C_BASE + SZ_4K - 1, + .flags = IORESOURCE_MEM, +}; + +struct platform_device realview_i2c_device = { + .name = "versatile-i2c", + .id = -1, + .num_resources = 1, + .resource = &realview_i2c_resource, +}; + #define REALVIEW_SYSMCI (__io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_MCI_OFFSET) static unsigned int realview_mmc_status(struct device *dev) diff --git a/arch/arm/mach-realview/core.h b/arch/arm/mach-realview/core.h index 93e86d9f439c..2b53420f9c1b 100644 --- a/arch/arm/mach-realview/core.h +++ b/arch/arm/mach-realview/core.h @@ -108,6 +108,7 @@ static struct amba_device name##_device = { \ extern struct platform_device realview_flash_device; extern struct platform_device realview_smc91x_device; +extern struct platform_device realview_i2c_device; extern struct mmc_platform_data realview_mmc0_plat_data; extern struct mmc_platform_data realview_mmc1_plat_data; extern struct clk realview_clcd_clk; diff --git a/arch/arm/mach-realview/realview_eb.c b/arch/arm/mach-realview/realview_eb.c index 84a959530fb6..9741b4d3c9cf 100644 --- a/arch/arm/mach-realview/realview_eb.c +++ b/arch/arm/mach-realview/realview_eb.c @@ -155,6 +155,7 @@ static void __init realview_eb_init(void) platform_device_register(&realview_flash_device); platform_device_register(&realview_smc91x_device); + platform_device_register(&realview_i2c_device); for (i = 0; i < ARRAY_SIZE(amba_devs); i++) { struct amba_device *d = amba_devs[i]; diff --git a/arch/arm/mach-versatile/core.c b/arch/arm/mach-versatile/core.c index 57196947559f..bf71507c76fd 100644 --- a/arch/arm/mach-versatile/core.c +++ b/arch/arm/mach-versatile/core.c @@ -325,6 +325,19 @@ static struct platform_device smc91x_device = { .resource = smc91x_resources, }; +static struct resource versatile_i2c_resource = { + .start = VERSATILE_I2C_BASE, + .end = VERSATILE_I2C_BASE + SZ_4K - 1, + .flags = IORESOURCE_MEM, +}; + +static struct platform_device versatile_i2c_device = { + .name = "versatile-i2c", + .id = -1, + .num_resources = 1, + .resource = &versatile_i2c_resource, +}; + #define VERSATILE_SYSMCI (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_MCI_OFFSET) unsigned int mmc_status(struct device *dev) @@ -775,6 +788,7 @@ void __init versatile_init(void) clk_register(&versatile_clcd_clk); platform_device_register(&versatile_flash_device); + platform_device_register(&versatile_i2c_device); platform_device_register(&smc91x_device); for (i = 0; i < ARRAY_SIZE(amba_devs); i++) { diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index ab398b700586..e1989f3a2684 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -476,6 +476,17 @@ config I2C_STUB If you don't know what to do here, definitely say N. +config I2C_VERSATILE + tristate "ARM Versatile/Realview I2C bus support" + depends on I2C && (ARCH_VERSATILE || ARCH_REALVIEW) + select I2C_ALGOBIT + help + Say yes if you want to support the I2C serial bus on ARMs Versatile + range of platforms. + + This driver can also be built as a module. If so, the module + will be called i2c-versatile. + config I2C_VIA tristate "VIA 82C586B" depends on I2C && PCI && EXPERIMENTAL diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index a82b6bfad046..37196c1d0794 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -40,6 +40,7 @@ obj-$(CONFIG_I2C_SIS5595) += i2c-sis5595.o obj-$(CONFIG_I2C_SIS630) += i2c-sis630.o obj-$(CONFIG_I2C_SIS96X) += i2c-sis96x.o obj-$(CONFIG_I2C_STUB) += i2c-stub.o +obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o obj-$(CONFIG_I2C_VIA) += i2c-via.o obj-$(CONFIG_I2C_VIAPRO) += i2c-viapro.o obj-$(CONFIG_I2C_VOODOO3) += i2c-voodoo3.o diff --git a/drivers/i2c/busses/i2c-versatile.c b/drivers/i2c/busses/i2c-versatile.c new file mode 100644 index 000000000000..081d9578ce10 --- /dev/null +++ b/drivers/i2c/busses/i2c-versatile.c @@ -0,0 +1,153 @@ +/* + * i2c-versatile.c + * + * Copyright (C) 2006 ARM Ltd. + * written by Russell King, Deep Blue Solutions Ltd. + * + * 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 +#include +#include +#include +#include +#include + +#include + +#define I2C_CONTROL 0x00 +#define I2C_CONTROLS 0x00 +#define I2C_CONTROLC 0x04 +#define SCL (1 << 0) +#define SDA (1 << 1) + +struct i2c_versatile { + struct i2c_adapter adap; + struct i2c_algo_bit_data algo; + void __iomem *base; +}; + +static void i2c_versatile_setsda(void *data, int state) +{ + struct i2c_versatile *i2c = data; + + writel(SDA, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC)); +} + +static void i2c_versatile_setscl(void *data, int state) +{ + struct i2c_versatile *i2c = data; + + writel(SCL, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC)); +} + +static int i2c_versatile_getsda(void *data) +{ + struct i2c_versatile *i2c = data; + return !!(readl(i2c->base + I2C_CONTROL) & SDA); +} + +static int i2c_versatile_getscl(void *data) +{ + struct i2c_versatile *i2c = data; + return !!(readl(i2c->base + I2C_CONTROL) & SCL); +} + +static struct i2c_algo_bit_data i2c_versatile_algo = { + .setsda = i2c_versatile_setsda, + .setscl = i2c_versatile_setscl, + .getsda = i2c_versatile_getsda, + .getscl = i2c_versatile_getscl, + .udelay = 30, + .timeout = HZ, +}; + +static int i2c_versatile_probe(struct platform_device *dev) +{ + struct i2c_versatile *i2c; + struct resource *r; + int ret; + + r = platform_get_resource(dev, IORESOURCE_MEM, 0); + if (!r) { + ret = -EINVAL; + goto err_out; + } + + if (!request_mem_region(r->start, r->end - r->start + 1, "versatile-i2c")) { + ret = -EBUSY; + goto err_out; + } + + i2c = kzalloc(sizeof(struct i2c_versatile), GFP_KERNEL); + if (!i2c) { + ret = -ENOMEM; + goto err_release; + } + + i2c->base = ioremap(r->start, r->end - r->start + 1); + if (!i2c->base) { + ret = -ENOMEM; + goto err_free; + } + + writel(SCL | SDA, i2c->base + I2C_CONTROLS); + + i2c->adap.owner = THIS_MODULE; + strlcpy(i2c->adap.name, "Versatile I2C adapter", sizeof(i2c->adap.name)); + i2c->adap.algo_data = &i2c->algo; + i2c->adap.dev.parent = &dev->dev; + i2c->algo = i2c_versatile_algo; + i2c->algo.data = i2c; + + ret = i2c_bit_add_bus(&i2c->adap); + if (ret >= 0) { + platform_set_drvdata(dev, i2c); + return 0; + } + + iounmap(i2c->base); + err_free: + kfree(i2c); + err_release: + release_mem_region(r->start, r->end - r->start + 1); + err_out: + return ret; +} + +static int i2c_versatile_remove(struct platform_device *dev) +{ + struct i2c_versatile *i2c = platform_get_drvdata(dev); + + platform_set_drvdata(dev, NULL); + + i2c_del_adapter(&i2c->adap); + return 0; +} + +static struct platform_driver i2c_versatile_driver = { + .probe = i2c_versatile_probe, + .remove = i2c_versatile_remove, + .driver = { + .name = "versatile-i2c", + .owner = THIS_MODULE, + }, +}; + +static int __init i2c_versatile_init(void) +{ + return platform_driver_register(&i2c_versatile_driver); +} + +static void __exit i2c_versatile_exit(void) +{ + platform_driver_unregister(&i2c_versatile_driver); +} + +module_init(i2c_versatile_init); +module_exit(i2c_versatile_exit); + +MODULE_DESCRIPTION("ARM Versatile I2C bus driver"); +MODULE_LICENSE("GPL");