> "Rajendra Nayak" <rnayak@xxxxxxxxxxxxxx> writes:
>
>>> On 23 April 2015 at 10:45, Rajendra Nayak <rnayak@xxxxxxxxxxxxxx>
>>> 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 <rnayak@xxxxxxxxxxxxxx>
>>>> Cc: <linux-mmc@xxxxxxxxxxxxxxx>
>>>> ---
>>>> drivers/mmc/host/sdhci-msm.c | 46
>>>> +++++++++++---------------------------------
>>>> 1 file changed, 11 insertions(+), 35 deletions(-)
>>>>
>>>> diff --git a/drivers/mmc/host/sdhci-msm.c
>>>> b/drivers/mmc/host/sdhci-msm.c
>>>> index 4a09f76..3c62a77 100644
>>>> --- a/drivers/mmc/host/sdhci-msm.c
>>>> +++ b/drivers/mmc/host/sdhci-msm.c
>>>> @@ -19,6 +19,7 @@
>>>> #include <linux/delay.h>
>>>> #include <linux/mmc/mmc.h>
>>>> #include <linux/slab.h>
>>>> +#include <linux/pm_runtime.h>
>>>>
>>>> #include "sdhci-pltfm.h"
>>>>
>>>> @@ -56,8 +57,6 @@
>>>> struct sdhci_msm_host {
>>>> struct platform_device *pdev;
>>>> void __iomem *core_mem; /* MSM SDCC mapped address */
>>>> - struct clk *clk; /* main SD/MMC bus clock */
>>>> - struct clk *pclk; /* SDHC peripheral bus clock */
>>>> struct clk *bus_clk; /* SDHC bus voter clock */
>>>> struct mmc_host *mmc;
>>>> struct sdhci_pltfm_data sdhci_msm_pdata;
>>>> @@ -469,29 +468,8 @@ static int sdhci_msm_probe(struct platform_device
>>>> *pdev)
>>>> goto pltfm_free;
>>>> }
>>>>
>>>> - /* Setup main peripheral bus clock */
>>>> - msm_host->pclk = devm_clk_get(&pdev->dev, "iface");
>>>> - if (IS_ERR(msm_host->pclk)) {
>>>> - ret = PTR_ERR(msm_host->pclk);
>>>> - dev_err(&pdev->dev, "Perpheral clk setup failed
>>>> (%d)\n",
>>>> ret);
>>>> - goto bus_clk_disable;
>>>> - }
>>>> -
>>>> - ret = clk_prepare_enable(msm_host->pclk);
>>>> - if (ret)
>>>> - goto bus_clk_disable;
>>>> -
>>>> - /* Setup SDC MMC clock */
>>>> - msm_host->clk = devm_clk_get(&pdev->dev, "core");
>>>> - if (IS_ERR(msm_host->clk)) {
>>>> - ret = PTR_ERR(msm_host->clk);
>>>> - dev_err(&pdev->dev, "SDC MMC clk setup failed (%d)\n",
>>>> ret);
>>>> - goto pclk_disable;
>>>> - }
>>>> -
>>>> - ret = clk_prepare_enable(msm_host->clk);
>>>> - if (ret)
>>>> - goto pclk_disable;
>>>> + pm_runtime_enable(&pdev->dev);
>>>> + pm_runtime_get_sync(&pdev->dev);
>>>>
>>>> core_memres = platform_get_resource(pdev, IORESOURCE_MEM, 1);
>>>> msm_host->core_mem = devm_ioremap_resource(&pdev->dev,
>>>> core_memres);
>>>> @@ -499,7 +477,7 @@ static int sdhci_msm_probe(struct platform_device
>>>> *pdev)
>>>> if (IS_ERR(msm_host->core_mem)) {
>>>> dev_err(&pdev->dev, "Failed to remap registers\n");
>>>> ret = PTR_ERR(msm_host->core_mem);
>>>> - goto clk_disable;
>>>> + goto err;
>>>> }
>>>>
>>>> /* Reset the core and Enable SDHC mode */
>>>> @@ -511,7 +489,7 @@ static int sdhci_msm_probe(struct platform_device
>>>> *pdev)
>>>> if (readl(msm_host->core_mem + CORE_POWER) & CORE_SW_RST) {
>>>> dev_err(&pdev->dev, "Stuck in reset\n");
>>>> ret = -ETIMEDOUT;
>>>> - goto clk_disable;
>>>> + goto err;
>>>> }
>>>>
>>>> /* Set HC_MODE_EN bit in HC_MODE register */
>>>> @@ -545,15 +523,13 @@ static int sdhci_msm_probe(struct
>>>> platform_device
>>>> *pdev)
>>>>
>>>> ret = sdhci_add_host(host);
>>>> if (ret)
>>>> - goto clk_disable;
>>>> + goto err;
>>>>
>>>> return 0;
>>>>
>>>> -clk_disable:
>>>> - clk_disable_unprepare(msm_host->clk);
>>>> -pclk_disable:
>>>> - clk_disable_unprepare(msm_host->pclk);
>>>> -bus_clk_disable:
>>>> +err:
>>>> + pm_runtime_put_sync(&pdev->dev);
>>>> + pm_runtime_disable(&pdev->dev);
>>>> if (!IS_ERR(msm_host->bus_clk))
>>>> clk_disable_unprepare(msm_host->bus_clk);
>>>> pltfm_free:
>>>> @@ -571,8 +547,8 @@ static int sdhci_msm_remove(struct platform_device
>>>> *pdev)
>>>>
>>>> sdhci_remove_host(host, dead);
>>>> sdhci_pltfm_free(pdev);
>>>> - clk_disable_unprepare(msm_host->clk);
>>>> - clk_disable_unprepare(msm_host->pclk);
>>>> + pm_runtime_put_sync(&pdev->dev);
>>>> + pm_runtime_disable(&pdev->dev);
>>>> if (!IS_ERR(msm_host->bus_clk))
>>>> clk_disable_unprepare(msm_host->bus_clk);
>>>> return 0;
[]..
>>>
>>> This all looks wrong. The driver will no longer work unless CONFIG_PM
>>> is
>>> set.
>>
>> Right, I seem to have completely ignored the !CONFIG_PM case.
>> Will look at how to handle that.
>
> IMO, don't complicate the driver with that. Just enable (or leave
> enabled) all the clocks in the clock driver in the !CONFIG_PM case.
so I just looked at what pm_clk_notify() does in !CONFIG_PM case and it
seems to do just that, leaves all the clocks enabled on
BUS_NOTIFY_BIND_DRIVER case and disables them for BUS_NOTIFY_UNBOUND_DRIVER
case. So looks like things are already in place to handle this :)
Ulf, does that address your concern or did I miss anything?
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