From: Ludovic Desroches <ludovic.desroches@xxxxxxxxx> Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx> --- .../devicetree/bindings/i2c/atmel-i2c.txt | 29 +++++++++++++ drivers/i2c/busses/i2c-at91.c | 49 +++++++++++++++++----- 2 files changed, 68 insertions(+), 10 deletions(-) create mode 100644 Documentation/devicetree/bindings/i2c/atmel-i2c.txt diff --git a/Documentation/devicetree/bindings/i2c/atmel-i2c.txt b/Documentation/devicetree/bindings/i2c/atmel-i2c.txt new file mode 100644 index 0000000..9e46289 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/atmel-i2c.txt @@ -0,0 +1,29 @@ +I2C for Atmel platforms + +Required properties : +- compatible : Must be "atmel,at91rm9200-i2c", "atmel,at91sam9261-i2c" or + "atmel,at91sam9g20-i2c" +- reg: physical base address of the controller and length of memory mapped + region. +- interrupts: interrupt number to the cpu. +- #address-cells = <1>; +- #size-cells = <0>; + +Optional properties: +- Child nodes conforming to i2c bus binding + +Examples : + +i2c0: i2c@fff84000 { + compatible = "atmel,at91sam9g20-i2c"; + reg = <0xfff84000 0x100>; + interrupts = <12 4>; + #address-cells = <1>; + #size-cells = <0>; + + 24c512@50 { + compatible = "24c512"; + reg = <0x50>; + pagesize = <128>; + } +} diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c index 4599522..1c86b24 100644 --- a/drivers/i2c/busses/i2c-at91.c +++ b/drivers/i2c/busses/i2c-at91.c @@ -24,6 +24,9 @@ #include <linux/interrupt.h> #include <linux/io.h> #include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_i2c.h> #include <linux/platform_device.h> #include <linux/slab.h> @@ -112,17 +115,27 @@ static void at91_init_twi_bus(struct at91_twi_dev *dev) */ static void __devinit at91_calc_twi_clock(struct at91_twi_dev *dev, int twi_clk) { - int offset, div, max_ckdiv, ckdiv, cdiv; - - if (cpu_is_at91rm9200()) { - offset = 3; - max_ckdiv = 5; - } else if (cpu_is_at91sam9261()) { - offset = 4; - max_ckdiv = 5; + int offset = 4, max_ckdiv = 7; + int div, ckdiv, cdiv; + + if (dev->dev->of_node) { + if (of_device_is_compatible(dev->dev->of_node, + "atmel,at91rm9200-i2c")) { + offset = 3; + max_ckdiv = 5; + } else if (of_device_is_compatible(dev->dev->of_node, + "atmel,at91sam9261-i2c")) { + offset = 4; + max_ckdiv = 5; + } } else { - offset = 4; - max_ckdiv = 7; + if (cpu_is_at91rm9200()) { + offset = 3; + max_ckdiv = 5; + } else if (cpu_is_at91sam9261()) { + offset = 4; + max_ckdiv = 5; + } } div = max(0, (int)DIV_ROUND_UP(clk_get_rate(dev->clk), @@ -379,6 +392,7 @@ static int __devinit at91_twi_probe(struct platform_device *pdev) dev->adapter.dev.parent = dev->dev; dev->adapter.nr = pdev->id; dev->adapter.timeout = AT91_I2C_TIMEOUT; + dev->adapter.dev.of_node = pdev->dev.of_node; rc = i2c_add_numbered_adapter(&dev->adapter); if (rc) { @@ -387,6 +401,8 @@ static int __devinit at91_twi_probe(struct platform_device *pdev) goto err_free_irq; } + of_i2c_register_devices(&dev->adapter); + dev_info(dev->dev, "AT91 i2c bus driver.\n"); return 0; @@ -454,12 +470,25 @@ static const struct dev_pm_ops at91_twi_pm = { #define at91_twi_pm_ops NULL #endif +#ifdef CONFIG_OF +static const struct of_device_id at91_twi_dt_ids[] = { + { .compatible = "atmel,at91rm9200-i2c", }, + { .compatible = "atmel,at91sam9260-i2c", }, + { .compatible = "atmel,at91sam9261-i2c", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, at91_twi_dt_ids); +#else +#define at91_twi_dt_ids NULL +#endif + static struct platform_driver at91_twi_driver = { .probe = at91_twi_probe, .remove = __devexit_p(at91_twi_remove), .driver = { .name = "at91_i2c", .owner = THIS_MODULE, + .of_match_table = at91_twi_dt_ids, .pm = at91_twi_pm_ops, }, }; -- 1.7.11.3 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html