Commit a8afc193 authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Greg Kroah-Hartman
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serial: 8250_dw: Use devm_clk_get_optional() to get the input clock 



Simplify the code which fetches the input clock by using
devm_clk_get_optional(). This comes with a small functional change: previously
all errors were ignored except deferred probe. Now all errors are
treated as errors. If no input clock is present devm_clk_get_optional() will
return NULL instead of an error which matches the behavior of the old code.

Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20190925162617.30368-1-andriy.shevchenko@linux.intel.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 254cc774

drivers/tty/serial/8250/8250_dw.c

+32 −43
Original line number Diff line number Diff line
@@ -280,9 +280,6 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios, 
	long rate;

	int ret;



	if (IS_ERR(d->clk))

		goto out;



	clk_disable_unprepare(d->clk);

	rate = clk_round_rate(d->clk, baud * 16);

	if (rate < 0)
@@ -293,7 +290,9 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios, 
		ret = clk_set_rate(d->clk, rate);

	clk_prepare_enable(d->clk);



	if (!ret)

	if (ret)

		goto out;



	p->uartclk = rate;



out:
@@ -472,19 +471,18 @@ static int dw8250_probe(struct platform_device *pdev) 
	device_property_read_u32(dev, "clock-frequency", &p->uartclk);



	/* If there is separate baudclk, get the rate from it. */

	data->clk = devm_clk_get(dev, "baudclk");

	if (IS_ERR(data->clk) && PTR_ERR(data->clk) != -EPROBE_DEFER)

		data->clk = devm_clk_get(dev, NULL);

	if (IS_ERR(data->clk) && PTR_ERR(data->clk) == -EPROBE_DEFER)

		return -EPROBE_DEFER;

	if (!IS_ERR_OR_NULL(data->clk)) {

	data->clk = devm_clk_get_optional(dev, "baudclk");

	if (data->clk == NULL)

		data->clk = devm_clk_get_optional(dev, NULL);

	if (IS_ERR(data->clk))

		return PTR_ERR(data->clk);



	err = clk_prepare_enable(data->clk);

	if (err)

			dev_warn(dev, "could not enable optional baudclk: %d\n",

				 err);

		else

		dev_warn(dev, "could not enable optional baudclk: %d\n", err);



	if (data->clk)

		p->uartclk = clk_get_rate(data->clk);

	}



	/* If no clock rate is defined, fail. */

	if (!p->uartclk) {
@@ -493,18 +491,17 @@ static int dw8250_probe(struct platform_device *pdev) 
		goto err_clk;

	}



	data->pclk = devm_clk_get(dev, "apb_pclk");

	if (IS_ERR(data->pclk) && PTR_ERR(data->pclk) == -EPROBE_DEFER) {

		err = -EPROBE_DEFER;

	data->pclk = devm_clk_get_optional(dev, "apb_pclk");

	if (IS_ERR(data->pclk)) {

		err = PTR_ERR(data->pclk);

		goto err_clk;

	}

	if (!IS_ERR(data->pclk)) {



	err = clk_prepare_enable(data->pclk);

	if (err) {

		dev_err(dev, "could not enable apb_pclk\n");

		goto err_clk;

	}

	}



	data->rst = devm_reset_control_get_optional_exclusive(dev, NULL);

	if (IS_ERR(data->rst)) {
@@ -546,11 +543,9 @@ err_reset: 
	reset_control_assert(data->rst);



err_pclk:

	if (!IS_ERR(data->pclk))

	clk_disable_unprepare(data->pclk);



err_clk:

	if (!IS_ERR(data->clk))

	clk_disable_unprepare(data->clk);



	return err;
@@ -567,10 +562,8 @@ static int dw8250_remove(struct platform_device *pdev) 


	reset_control_assert(data->rst);



	if (!IS_ERR(data->pclk))

	clk_disable_unprepare(data->pclk);



	if (!IS_ERR(data->clk))

	clk_disable_unprepare(data->clk);



	pm_runtime_disable(dev);
@@ -604,10 +597,8 @@ static int dw8250_runtime_suspend(struct device *dev) 
{

	struct dw8250_data *data = dev_get_drvdata(dev);



	if (!IS_ERR(data->clk))

	clk_disable_unprepare(data->clk);



	if (!IS_ERR(data->pclk))

	clk_disable_unprepare(data->pclk);



	return 0;
@@ -617,10 +608,8 @@ static int dw8250_runtime_resume(struct device *dev) 
{

	struct dw8250_data *data = dev_get_drvdata(dev);



	if (!IS_ERR(data->pclk))

	clk_prepare_enable(data->pclk);



	if (!IS_ERR(data->clk))

	clk_prepare_enable(data->clk);



	return 0;

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