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i2c: nomadik: Add Device Tree support to the Nomadik I2C driver 

Here we apply the bindings required for successful Device Tree
probing of the i2c-nomadik driver.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
This commit is contained in:
Lee Jones 2012-08-06 11:09:57 +01:00 committed by Wolfram Sang
parent a76e7c6821
commit 43fea5813c
3 changed files with 56 additions and 4 deletions
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23
Documentation/devicetree/bindings/i2c/nomadik.txt Normal file
View File

@ -0,0 +1,23 @@
I2C for Nomadik based systems
Required (non-standard) properties:
- Nil
Recommended (non-standard) properties:
- clock-frequency : Maximum bus clock frequency for the device
Optional (non-standard) properties:
- Nil
Example :
i2c@80004000 {
compatible = "stericsson,db8500-i2c", "st,nomadik-i2c";
reg = <0x80004000 0x1000>;
interrupts = <0 21 0x4>;
#address-cells = <1>;
#size-cells = <0>;
v-i2c-supply = <&db8500_vape_reg>;
clock-frequency = <400000>;
};

35
drivers/i2c/busses/i2c-nomadik.c
View File

@ -24,6 +24,8 @@
#include <linux/io.h>
#include <linux/pm_runtime.h>
#include <linux/platform_data/i2c-nomadik.h>
#include <linux/of.h>
#include <linux/of_i2c.h>
#define DRIVER_NAME "nmk-i2c"
@ -913,18 +915,42 @@ static struct nmk_i2c_controller u8500_i2c = {
.sm = I2C_FREQ_MODE_FAST,
};
static void nmk_i2c_of_probe(struct device_node *np,
struct nmk_i2c_controller *pdata)
{
of_property_read_u32(np, "clock-frequency", &pdata->clk_freq);
/* This driver only supports 'standard' and 'fast' modes of operation. */
if (pdata->clk_freq <= 100000)
pdata->sm = I2C_FREQ_MODE_STANDARD;
else
pdata->sm = I2C_FREQ_MODE_FAST;
}
static atomic_t adapter_id = ATOMIC_INIT(0);
static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
{
int ret = 0;
struct nmk_i2c_controller *pdata = adev->dev.platform_data;
struct device_node *np = adev->dev.of_node;
struct nmk_i2c_dev *dev;
struct i2c_adapter *adap;
if (!pdata)
/* No i2c configuration found, using the default. */
pdata = &u8500_i2c;
if (!pdata) {
if (np) {
pdata = devm_kzalloc(&adev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata) {
ret = -ENOMEM;
goto err_no_mem;
}
/* Provide the default configuration as a base. */
memcpy(pdata, &u8500_i2c, sizeof(struct nmk_i2c_controller));
nmk_i2c_of_probe(np, pdata);
} else
/* No i2c configuration found, using the default. */
pdata = &u8500_i2c;
}
dev = kzalloc(sizeof(struct nmk_i2c_dev), GFP_KERNEL);
if (!dev) {
@ -960,6 +986,7 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
}
adap = &dev->adap;
adap->dev.of_node = np;
adap->dev.parent = &adev->dev;
adap->owner = THIS_MODULE;
adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
@ -989,6 +1016,8 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
goto err_add_adap;
}
of_i2c_register_devices(adap);
pm_runtime_put(&adev->dev);
return 0;

2
include/linux/platform_data/i2c-nomadik.h
View File

@ -28,7 +28,7 @@ enum i2c_freq_mode {
* @sm: speed mode
*/
struct nmk_i2c_controller {
unsigned long clk_freq;
u32 clk_freq;
unsigned short slsu;
unsigned char tft;
unsigned char rft;