Subject: [RFC/RFT 3/6] serial: msm: convert driver to use runtime PM apis

From: [email-masked] (Rajendra Nayak)
Date: Wed, 29 Apr 2015 08:45:54 +0530

On 04/29/2015 05:46 AM, Stephen Boyd wrote:
> On 04/23/15 01:45, Rajendra Nayak wrote:
>> With platform support now in place to manage clocks from within runtime PM
>> callbacks, get rid of all clock handling from the driver and convert the
>> driver to use runtime PM apis.
>>
>> Signed-off-by: Rajendra Nayak <[email-masked]>
>> Cc: <[email-masked]>
>
> Pramod is changing the same file in the same area. Please work together
> if necessary.

Sure, will do. For some reason I thought those changes already made it
in 4.1, but maybe not.

>
> -Stephen
>
>> ---
>>   drivers/tty/serial/msm_serial.c | 33 ++++++++++++++++-----------------
>>   1 file changed, 16 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
>> index b73889c..eb66502 100644
>> --- a/drivers/tty/serial/msm_serial.c
>> +++ b/drivers/tty/serial/msm_serial.c
>> @@ -33,6 +33,7 @@
>>   #include <linux/serial.h>
>>   #include <linux/clk.h>
>>   #include <linux/platform_device.h>
>> +#include <linux/pm_runtime.h>
>>   #include <linux/delay.h>
>>   #include <linux/of.h>
>>   #include <linux/of_device.h>
>> @@ -50,11 +51,11 @@ struct msm_port {
>>   	struct uart_port	uart;
>>   	char			name[16];
>>   	struct clk		*clk;
>> -	struct clk		*pclk;
>>   	unsigned int		imr;
>>   	int			is_uartdm;
>>   	unsigned int		old_snap_state;
>>   	bool			break_detected;
>> +	struct device		*dev;
>>   };
>>
>>   static inline void wait_for_xmitr(struct uart_port *port)
>> @@ -464,12 +465,11 @@ static int msm_set_baud_rate(struct uart_port *port, unsigned int baud)
>>   	return baud;
>>   }
>>
>> -static void msm_init_clock(struct uart_port *port)
>> +static void msm_init(struct uart_port *port)
>>   {
>>   	struct msm_port *msm_port = UART_TO_MSM(port);
>>
>> -	clk_prepare_enable(msm_port->clk);
>> -	clk_prepare_enable(msm_port->pclk);
>> +	pm_runtime_get_sync(msm_port->dev);
>>   	msm_serial_set_mnd_regs(port);
>>   }
>>
>> @@ -487,7 +487,7 @@ static int msm_startup(struct uart_port *port)
>>   	if (unlikely(ret))
>>   		return ret;
>>
>> -	msm_init_clock(port);
>> +	msm_init(port);
>>
>>   	if (likely(port->fifosize > 12))
>>   		rfr_level = port->fifosize - 12;
>> @@ -511,7 +511,7 @@ static void msm_shutdown(struct uart_port *port)
>>   	msm_port->imr = 0;
>>   	msm_write(port, 0, UART_IMR); /* disable interrupts */
>>
>> -	clk_disable_unprepare(msm_port->clk);
>> +	pm_runtime_put_sync(msm_port->dev);
>>
>>   	free_irq(port->irq, port);
>>   }
>> @@ -669,12 +669,10 @@ static void msm_power(struct uart_port *port, unsigned int state,
>>
>>   	switch (state) {
>>   	case 0:
>> -		clk_prepare_enable(msm_port->clk);
>> -		clk_prepare_enable(msm_port->pclk);
>> +		pm_runtime_get_sync(msm_port->dev);
>>   		break;
>>   	case 3:
>> -		clk_disable_unprepare(msm_port->clk);
>> -		clk_disable_unprepare(msm_port->pclk);
>> +		pm_runtime_put_sync(msm_port->dev);
>>   		break;
>>   	default:
>>   		pr_err("msm_serial: Unknown PM state %d\n", state);
>> @@ -933,7 +931,7 @@ static int __init msm_console_setup(struct console *co, char *options)
>>   	if (unlikely(!port->membase))
>>   		return -ENXIO;
>>
>> -	msm_init_clock(port);
>> +	msm_init(port);
>>
>>   	if (options)
>>   		uart_parse_options(options, &baud, &parity, &bits, &flow);
>> @@ -1057,13 +1055,10 @@ static int msm_serial_probe(struct platform_device *pdev)
>>   	if (IS_ERR(msm_port->clk))
>>   		return PTR_ERR(msm_port->clk);
>>
>> -	if (msm_port->is_uartdm) {
>> -		msm_port->pclk = devm_clk_get(&pdev->dev, "iface");
>> -		if (IS_ERR(msm_port->pclk))
>> -			return PTR_ERR(msm_port->pclk);
>> -
>> +	if (msm_port->is_uartdm)
>>   		clk_set_rate(msm_port->clk, 1843200);
>> -	}
>> +
>> +	msm_port->dev = &pdev->dev;
>>
>>   	port->uartclk = clk_get_rate(msm_port->clk);
>>   	dev_info(&pdev->dev, "uartclk = %d\n", port->uartclk);
>> @@ -1080,13 +1075,17 @@ static int msm_serial_probe(struct platform_device *pdev)
>>
>>   	platform_set_drvdata(pdev, port);
>>
>> +	pm_runtime_enable(&pdev->dev);
>> +
>>   	return uart_add_one_port(&msm_uart_driver, port);
>>   }
>>
>>   static int msm_serial_remove(struct platform_device *pdev)
>>   {
>>   	struct uart_port *port = platform_get_drvdata(pdev);
>> +	struct msm_port *msm_port = UART_TO_MSM(port);
>>
>> +	pm_runtime_disable(msm_port->dev);
>>   	uart_remove_one_port(&msm_uart_driver, port);
>>
>>   	return 0;
>
>

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