[RFC/RFT 5/6] i2c: qup: Get rid of clock handling as its done using runtime callbacks

[Ivan T. Ivanov]

Hi Rajendra,

> On Apr 23, 2015, at 11:45 AM, Rajendra Nayak <rnayak at codeaurora.org> wrote:
> 
> Remove all clock handling from the driver as this is not handled from
> within platform runtime callbacks.
> 
> Signed-off-by: Rajendra Nayak <rnayak at codeaurora.org>
> ---
> drivers/i2c/busses/i2c-qup.c | 74 ++++++++++----------------------------------
> 1 file changed, 16 insertions(+), 58 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c
> index fdcbdab..465a2b2 100644
> --- a/drivers/i2c/busses/i2c-qup.c
> +++ b/drivers/i2c/busses/i2c-qup.c
> @@ -104,7 +104,6 @@ struct qup_i2c_dev {
> 	void __iomem		*base;
> 	int			irq;
> 	struct clk		*clk;
> -	struct clk		*pclk;
> 	struct i2c_adapter	adap;
> 
> 	int			clk_ctl;
> @@ -532,24 +531,6 @@ static struct i2c_adapter_quirks qup_i2c_quirks = {
> 	.max_read_len = QUP_READ_LIMIT,
> };
> 
> -static void qup_i2c_enable_clocks(struct qup_i2c_dev *qup)
> -{
> -	clk_prepare_enable(qup->clk);
> -	clk_prepare_enable(qup->pclk);
> -}
> -
> -static void qup_i2c_disable_clocks(struct qup_i2c_dev *qup)
> -{
> -	u32 config;
> -
> -	qup_i2c_change_state(qup, QUP_RESET_STATE);
> -	clk_disable_unprepare(qup->clk);
> -	config = readl(qup->base + QUP_CONFIG);
> -	config |= QUP_CLOCK_AUTO_GATE;
> -	writel(config, qup->base + QUP_CONFIG);
> -	clk_disable_unprepare(qup->pclk);
> -}
> -
> static int qup_i2c_probe(struct platform_device *pdev)
> {
> 	static const int blk_sizes[] = {4, 16, 32};
> @@ -596,13 +577,10 @@ static int qup_i2c_probe(struct platform_device *pdev)
> 		return PTR_ERR(qup->clk);
> 	}
> 
> -	qup->pclk = devm_clk_get(qup->dev, "iface");
> -	if (IS_ERR(qup->pclk)) {
> -		dev_err(qup->dev, "Could not get iface clock\n");
> -		return PTR_ERR(qup->pclk);
> -	}
> -
> -	qup_i2c_enable_clocks(qup);
> +	pm_runtime_set_autosuspend_delay(qup->dev, MSEC_PER_SEC);
> +	pm_runtime_use_autosuspend(qup->dev);
> +	pm_runtime_enable(qup->dev);
> +	pm_runtime_get_sync(qup->dev);
> 
> 	/*
> 	 * Bootloaders might leave a pending interrupt on certain QUP's,
> @@ -673,22 +651,15 @@ static int qup_i2c_probe(struct platform_device *pdev)
> 	qup->adap.dev.of_node = pdev->dev.of_node;
> 	strlcpy(qup->adap.name, "QUP I2C adapter", sizeof(qup->adap.name));
> 
> -	pm_runtime_set_autosuspend_delay(qup->dev, MSEC_PER_SEC);
> -	pm_runtime_use_autosuspend(qup->dev);
> -	pm_runtime_set_active(qup->dev);
> -	pm_runtime_enable(qup->dev);
> -
> 	ret = i2c_add_adapter(&qup->adap);
> 	if (ret)
> -		goto fail_runtime;
> +		goto fail;
> 
> 	return 0;
> 
> -fail_runtime:
> +fail:
> 	pm_runtime_disable(qup->dev);
> 	pm_runtime_set_suspended(qup->dev);
> -fail:
> -	qup_i2c_disable_clocks(qup);
> 	return ret;
> }


Same thing like in MMC driver. Clocks should be explicitly
enabled because CONFIG_PM could be off.

Thanks,
Ivan