[PATCH v2] mmc: atmel-mci: add runtime pm support
Ulf Hansson
ulf.hansson at linaro.org
Tue Nov 4 02:05:56 PST 2014
On 30 October 2014 05:00, Wenyou Yang <wenyou.yang at atmel.com> wrote:
> Add runtime pm support to atmel mci controller.
> Use runtime pm APIs to enable/disable atmel mci's clock.
> Use runtime autosuspend APIs to enable auto suspend delay.
>
> Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
Ludovic, any objections to this one?
Kind regards
Uffe
> ---
> Changes v1 -> v2:
> * Adjust the APIs and invoking sequence to avoid clock unbalance issue during ->probe.
> * Fix miss to invoke clk_disable_unprepare() in the error handling in ->probe.
> * Remove atmci_suspend/resume and use pm_runtime_force_suspend/resume() to simplify code.
>
> drivers/mmc/host/atmel-mci.c | 90 +++++++++++++++++++++++++++++++-----------
> 1 file changed, 67 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
> index 0b9ddf8..f8f2bbe 100644
> --- a/drivers/mmc/host/atmel-mci.c
> +++ b/drivers/mmc/host/atmel-mci.c
> @@ -37,6 +37,8 @@
>
> #include <linux/atmel-mci.h>
> #include <linux/atmel_pdc.h>
> +#include <linux/pm.h>
> +#include <linux/pm_runtime.h>
>
> #include <asm/cacheflush.h>
> #include <asm/io.h>
> @@ -44,6 +46,8 @@
>
> #include "atmel-mci-regs.h"
>
> +#define AUTOSUSPEND_DELAY 50
> +
> #define ATMCI_DATA_ERROR_FLAGS (ATMCI_DCRCE | ATMCI_DTOE | ATMCI_OVRE | ATMCI_UNRE)
> #define ATMCI_DMA_THRESHOLD 16
>
> @@ -386,20 +390,19 @@ static int atmci_regs_show(struct seq_file *s, void *v)
> if (!buf)
> return -ENOMEM;
>
> + pm_runtime_get_sync(&host->pdev->dev);
> +
> /*
> * Grab a more or less consistent snapshot. Note that we're
> * not disabling interrupts, so IMR and SR may not be
> * consistent.
> */
> - ret = clk_prepare_enable(host->mck);
> - if (ret)
> - goto out;
> -
> spin_lock_bh(&host->lock);
> memcpy_fromio(buf, host->regs, ATMCI_REGS_SIZE);
> spin_unlock_bh(&host->lock);
>
> - clk_disable_unprepare(host->mck);
> + pm_runtime_mark_last_busy(&host->pdev->dev);
> + pm_runtime_put_autosuspend(&host->pdev->dev);
>
> seq_printf(s, "MR:\t0x%08x%s%s ",
> buf[ATMCI_MR / 4],
> @@ -449,7 +452,6 @@ static int atmci_regs_show(struct seq_file *s, void *v)
> val & ATMCI_CFG_LSYNC ? " LSYNC" : "");
> }
>
> -out:
> kfree(buf);
>
> return ret;
> @@ -1252,6 +1254,8 @@ static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
> WARN_ON(slot->mrq);
> dev_dbg(&host->pdev->dev, "MRQ: cmd %u\n", mrq->cmd->opcode);
>
> + pm_runtime_get_sync(&host->pdev->dev);
> +
> /*
> * We may "know" the card is gone even though there's still an
> * electrical connection. If so, we really need to communicate
> @@ -1281,7 +1285,8 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> struct atmel_mci_slot *slot = mmc_priv(mmc);
> struct atmel_mci *host = slot->host;
> unsigned int i;
> - bool unprepare_clk;
> +
> + pm_runtime_get_sync(&host->pdev->dev);
>
> slot->sdc_reg &= ~ATMCI_SDCBUS_MASK;
> switch (ios->bus_width) {
> @@ -1297,13 +1302,8 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> unsigned int clock_min = ~0U;
> u32 clkdiv;
>
> - clk_prepare(host->mck);
> - unprepare_clk = true;
> -
> spin_lock_bh(&host->lock);
> if (!host->mode_reg) {
> - clk_enable(host->mck);
> - unprepare_clk = false;
> atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
> atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
> if (host->caps.has_cfg_reg)
> @@ -1371,8 +1371,6 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> } else {
> bool any_slot_active = false;
>
> - unprepare_clk = false;
> -
> spin_lock_bh(&host->lock);
> slot->clock = 0;
> for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
> @@ -1385,17 +1383,12 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
> if (host->mode_reg) {
> atmci_readl(host, ATMCI_MR);
> - clk_disable(host->mck);
> - unprepare_clk = true;
> }
> host->mode_reg = 0;
> }
> spin_unlock_bh(&host->lock);
> }
>
> - if (unprepare_clk)
> - clk_unprepare(host->mck);
> -
> switch (ios->power_mode) {
> case MMC_POWER_OFF:
> if (!IS_ERR(mmc->supply.vmmc))
> @@ -1421,6 +1414,9 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> */
> break;
> }
> +
> + pm_runtime_mark_last_busy(&host->pdev->dev);
> + pm_runtime_put_autosuspend(&host->pdev->dev);
> }
>
> static int atmci_get_ro(struct mmc_host *mmc)
> @@ -1512,6 +1508,9 @@ static void atmci_request_end(struct atmel_mci *host, struct mmc_request *mrq)
> spin_unlock(&host->lock);
> mmc_request_done(prev_mmc, mrq);
> spin_lock(&host->lock);
> +
> + pm_runtime_mark_last_busy(&host->pdev->dev);
> + pm_runtime_put_autosuspend(&host->pdev->dev);
> }
>
> static void atmci_command_complete(struct atmel_mci *host,
> @@ -2417,15 +2416,16 @@ static int __init atmci_probe(struct platform_device *pdev)
>
> atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
> host->bus_hz = clk_get_rate(host->mck);
> - clk_disable_unprepare(host->mck);
>
> host->mapbase = regs->start;
>
> tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)host);
>
> ret = request_irq(irq, atmci_interrupt, 0, dev_name(&pdev->dev), host);
> - if (ret)
> + if (ret) {
> + clk_disable_unprepare(host->mck);
> return ret;
> + }
>
> /* Get MCI capabilities and set operations according to it */
> atmci_get_cap(host);
> @@ -2449,6 +2449,12 @@ static int __init atmci_probe(struct platform_device *pdev)
>
> setup_timer(&host->timer, atmci_timeout_timer, (unsigned long)host);
>
> + pm_runtime_get_noresume(&pdev->dev);
> + pm_runtime_set_active(&pdev->dev);
> + pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_DELAY);
> + pm_runtime_use_autosuspend(&pdev->dev);
> + pm_runtime_enable(&pdev->dev);
> +
> /* We need at least one slot to succeed */
> nr_slots = 0;
> ret = -ENODEV;
> @@ -2491,6 +2497,9 @@ static int __init atmci_probe(struct platform_device *pdev)
> "Atmel MCI controller at 0x%08lx irq %d, %u slots\n",
> host->mapbase, irq, nr_slots);
>
> + pm_runtime_mark_last_busy(&host->pdev->dev);
> + pm_runtime_put_autosuspend(&pdev->dev);
> +
> return 0;
>
> err_dma_alloc:
> @@ -2499,6 +2508,11 @@ err_dma_alloc:
> atmci_cleanup_slot(host->slot[i], i);
> }
> err_init_slot:
> + clk_disable_unprepare(host->mck);
> +
> + pm_runtime_disable(&pdev->dev);
> + pm_runtime_put_noidle(&pdev->dev);
> +
> del_timer_sync(&host->timer);
> if (host->dma.chan)
> dma_release_channel(host->dma.chan);
> @@ -2511,6 +2525,8 @@ static int __exit atmci_remove(struct platform_device *pdev)
> struct atmel_mci *host = platform_get_drvdata(pdev);
> unsigned int i;
>
> + pm_runtime_get_sync(&pdev->dev);
> +
> if (host->buffer)
> dma_free_coherent(&pdev->dev, host->buf_size,
> host->buffer, host->buf_phys_addr);
> @@ -2520,11 +2536,9 @@ static int __exit atmci_remove(struct platform_device *pdev)
> atmci_cleanup_slot(host->slot[i], i);
> }
>
> - clk_prepare_enable(host->mck);
> atmci_writel(host, ATMCI_IDR, ~0UL);
> atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
> atmci_readl(host, ATMCI_SR);
> - clk_disable_unprepare(host->mck);
>
> del_timer_sync(&host->timer);
> if (host->dma.chan)
> @@ -2532,14 +2546,44 @@ static int __exit atmci_remove(struct platform_device *pdev)
>
> free_irq(platform_get_irq(pdev, 0), host);
>
> + clk_disable_unprepare(host->mck);
> +
> + pm_runtime_disable(&pdev->dev);
> + pm_runtime_put_noidle(&pdev->dev);
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int atmci_runtime_suspend(struct device *dev)
> +{
> + struct atmel_mci *host = dev_get_drvdata(dev);
> +
> + clk_disable_unprepare(host->mck);
> +
> return 0;
> }
>
> +static int atmci_runtime_resume(struct device *dev)
> +{
> + struct atmel_mci *host = dev_get_drvdata(dev);
> +
> + return clk_prepare_enable(host->mck);
> +}
> +
> +static const struct dev_pm_ops atmci_dev_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> + pm_runtime_force_resume)
> + SET_PM_RUNTIME_PM_OPS(atmci_runtime_suspend, atmci_runtime_resume, NULL)
> +};
> +#endif
> +
> static struct platform_driver atmci_driver = {
> .remove = __exit_p(atmci_remove),
> .driver = {
> .name = "atmel_mci",
> .of_match_table = of_match_ptr(atmci_dt_ids),
> + .pm = &atmci_dev_pm_ops,
> },
> };
>
> --
> 1.7.9.5
>
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