i2c: ocores: add common clock support

Allow bus clock specification as a common clock handle. This makes this
controller easier to use in a setup based on common clock framework.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Max Filippov
2015-02-05 22:55:01 +03:00
committed by Wolfram Sang
parent 181d9a07da
commit e961a094af
2 changed files with 59 additions and 6 deletions

View File

@@ -12,6 +12,7 @@
* kind, whether express or implied.
*/
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
@@ -35,6 +36,7 @@ struct ocores_i2c {
int pos;
int nmsgs;
int state; /* see STATE_ */
struct clk *clk;
int ip_clock_khz;
int bus_clock_khz;
void (*setreg)(struct ocores_i2c *i2c, int reg, u8 value);
@@ -339,7 +341,21 @@ static int ocores_i2c_of_probe(struct platform_device *pdev,
&clock_frequency);
i2c->bus_clock_khz = 100;
if (of_property_read_u32(np, "opencores,ip-clock-frequency", &val)) {
i2c->clk = devm_clk_get(&pdev->dev, NULL);
if (!IS_ERR(i2c->clk)) {
int ret = clk_prepare_enable(i2c->clk);
if (ret) {
dev_err(&pdev->dev,
"clk_prepare_enable failed: %d\n", ret);
return ret;
}
i2c->ip_clock_khz = clk_get_rate(i2c->clk) / 1000;
if (clock_frequency_present)
i2c->bus_clock_khz = clock_frequency / 1000;
} else if (of_property_read_u32(np, "opencores,ip-clock-frequency",
&val)) {
if (!clock_frequency_present) {
dev_err(&pdev->dev,
"Missing required parameter 'opencores,ip-clock-frequency'\n");
@@ -477,6 +493,9 @@ static int ocores_i2c_remove(struct platform_device *pdev)
/* remove adapter & data */
i2c_del_adapter(&i2c->adap);
if (!IS_ERR(i2c->clk))
clk_disable_unprepare(i2c->clk);
return 0;
}
@@ -489,6 +508,8 @@ static int ocores_i2c_suspend(struct device *dev)
/* make sure the device is disabled */
oc_setreg(i2c, OCI2C_CONTROL, ctrl & ~(OCI2C_CTRL_EN|OCI2C_CTRL_IEN));
if (!IS_ERR(i2c->clk))
clk_disable_unprepare(i2c->clk);
return 0;
}
@@ -496,6 +517,16 @@ static int ocores_i2c_resume(struct device *dev)
{
struct ocores_i2c *i2c = dev_get_drvdata(dev);
if (!IS_ERR(i2c->clk)) {
int ret = clk_prepare_enable(i2c->clk);
if (ret) {
dev_err(dev,
"clk_prepare_enable failed: %d\n", ret);
return ret;
}
i2c->ip_clock_khz = clk_get_rate(i2c->clk) / 1000;
}
return ocores_init(dev, i2c);
}