Commit d303ce59 authored by Geert Uytterhoeven's avatar Geert Uytterhoeven Committed by Wolfram Sang
Browse files

i2c: riic: Add Runtime PM support 



- Replace explicit clock handling by Runtime PM calls,
  - Streamline Runtime PM handling in error paths,
  - Enable Runtime PM in .probe(),
  - Disable Runtime PM in .remove(),
  - Make sure the device is runtime-resumed when disabling interrupts in
    .remove().

Signed-off-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: default avatarNiklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: default avatarChris Brandt <chris.brandt@renesas.com>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent 18073da7

drivers/i2c/busses/i2c-riic.c

+24 −19
Original line number Diff line number Diff line
@@ -43,6 +43,7 @@ 
#include <linux/module.h>

#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/pm_runtime.h>



#define RIIC_ICCR1	0x00

#define RIIC_ICCR2	0x04
@@ -112,12 +113,10 @@ static int riic_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) 
{

	struct riic_dev *riic = i2c_get_adapdata(adap);

	unsigned long time_left;

	int i, ret;

	int i;

	u8 start_bit;



	ret = clk_prepare_enable(riic->clk);

	if (ret)

		return ret;

	pm_runtime_get_sync(adap->dev.parent);



	if (readb(riic->base + RIIC_ICCR2) & ICCR2_BBSY) {

		riic->err = -EBUSY;
@@ -150,7 +149,7 @@ static int riic_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) 
	}



 out:

	clk_disable_unprepare(riic->clk);

	pm_runtime_put(adap->dev.parent);



	return riic->err ?: num;

}
@@ -281,20 +280,18 @@ static const struct i2c_algorithm riic_algo = { 


static int riic_init_hw(struct riic_dev *riic, struct i2c_timings *t)

{

	int ret;

	int ret = 0;

	unsigned long rate;

	int total_ticks, cks, brl, brh;



	ret = clk_prepare_enable(riic->clk);

	if (ret)

		return ret;

	pm_runtime_get_sync(riic->adapter.dev.parent);



	if (t->bus_freq_hz > 400000) {

		dev_err(&riic->adapter.dev,

			"unsupported bus speed (%dHz). 400000 max\n",

			t->bus_freq_hz);

		clk_disable_unprepare(riic->clk);

		return -EINVAL;

		ret = -EINVAL;

		goto out;

	}



	rate = clk_get_rate(riic->clk);
@@ -332,8 +329,8 @@ static int riic_init_hw(struct riic_dev *riic, struct i2c_timings *t) 
	if (brl > (0x1F + 3)) {

		dev_err(&riic->adapter.dev, "invalid speed (%lu). Too slow.\n",

			(unsigned long)t->bus_freq_hz);

		clk_disable_unprepare(riic->clk);

		return -EINVAL;

		ret = -EINVAL;

		goto out;

	}



	brh = total_ticks - brl;
@@ -378,9 +375,9 @@ static int riic_init_hw(struct riic_dev *riic, struct i2c_timings *t) 


	riic_clear_set_bit(riic, ICCR1_IICRST, 0, RIIC_ICCR1);



	clk_disable_unprepare(riic->clk);



	return 0;

out:

	pm_runtime_put(riic->adapter.dev.parent);

	return ret;

}



static struct riic_irq_desc riic_irqs[] = {
@@ -439,28 +436,36 @@ static int riic_i2c_probe(struct platform_device *pdev) 


	i2c_parse_fw_timings(&pdev->dev, &i2c_t, true);



	pm_runtime_enable(&pdev->dev);



	ret = riic_init_hw(riic, &i2c_t);

	if (ret)

		return ret;



		goto out;



	ret = i2c_add_adapter(adap);

	if (ret)

		return ret;

		goto out;



	platform_set_drvdata(pdev, riic);



	dev_info(&pdev->dev, "registered with %dHz bus speed\n",

		 i2c_t.bus_freq_hz);

	return 0;



out:

	pm_runtime_disable(&pdev->dev);

	return ret;

}



static int riic_i2c_remove(struct platform_device *pdev)

{

	struct riic_dev *riic = platform_get_drvdata(pdev);



	pm_runtime_get_sync(&pdev->dev);

	writeb(0, riic->base + RIIC_ICIER);

	pm_runtime_put(&pdev->dev);

	i2c_del_adapter(&riic->adapter);

	pm_runtime_disable(&pdev->dev);



	return 0;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE