[PATCH v2 3/5] mmc: mediatek: Add PM support for MMC driver

Chaotian Jing
2015-03-17T03:13:53Z

Add PM support for Mediatek MMC driver

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
---
drivers/mmc/host/mtk-sd.c | 94 ++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 93 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index 86c999b..e02f6a6 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -21,6 +21,7 @@
#include <linux/of_irq.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/spinlock.h>

@@ -223,6 +224,7 @@
#define MSDC_OCR_AVAIL (MMC_VDD_28_29 | MMC_VDD_29_30 \
| MMC_VDD_30_31 | MMC_VDD_31_32 | MMC_VDD_32_33)

+#define MTK_MMC_AUTOSUSPEND_DELAY 500
#define CMD_TIMEOUT (HZ/10 * 5) /* 100ms x5 */
#define DAT_TIMEOUT (HZ * 5) /* 1000ms x5 */

@@ -535,6 +537,38 @@ static void msdc_set_mclk(struct msdc_host *host, int ddr, u32 hz)
dev_dbg(host->dev, "sclk: %d, ddr: %d\n", host->sclk, ddr);
}

+#ifdef CONFIG_PM
+static int msdc_gate_clock(struct msdc_host *host)
+{
+ int ret = 0;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+ /* disable SD/MMC/SDIO bus clock */
+ sdr_set_field(host->base + MSDC_CFG, MSDC_CFG_MODE, MSDC_MS);
+ /* turn off SDHC functional clock */
+ clk_disable(host->src_clk);
+ spin_unlock_irqrestore(&host->lock, flags);
+ return ret;
+}
+
+static void msdc_ungate_clock(struct msdc_host *host)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+ clk_enable(host->src_clk);
+ /* enable SD/MMC/SDIO bus clock:
+ * it will be automatically gated when the bus is idle
+ * (set MSDC_CFG_CKPDN bit to have it always on)
+ */
+ sdr_set_field(host->base + MSDC_CFG, MSDC_CFG_MODE, MSDC_SDMMC);
+ while (!(readl(host->base + MSDC_CFG) & MSDC_CFG_CKSTB))
+ cpu_relax();
+ spin_unlock_irqrestore(&host->lock, flags);
+}
+#endif
+
static inline u32 msdc_cmd_find_resp(struct msdc_host *host,
struct mmc_request *mrq, struct mmc_command *cmd)
{
@@ -702,6 +736,9 @@ static void msdc_request_done(struct msdc_host *host, struct mmc_request *mrq)
if (mrq->data)
msdc_unprepare_data(host, mrq);
mmc_request_done(host->mmc, mrq);
+
+ pm_runtime_mark_last_busy(host->dev);
+ pm_runtime_put_autosuspend(host->dev);
}

/* returns true if command is fully handled; returns false otherwise */
@@ -863,6 +900,8 @@ static void msdc_ops_request(struct mmc_host *mmc, struct mmc_request *mrq)
}
spin_unlock_irqrestore(&host->lock, flags);

+ pm_runtime_get_sync(host->dev);
+
if (mrq->data)
msdc_prepare_data(host, mrq);

@@ -1003,6 +1042,8 @@ static int msdc_ops_switch_volt(struct mmc_host *mmc, struct mmc_ios *ios)

if (!IS_ERR(mmc->supply.vqmmc)) {

+ pm_runtime_get_sync(host->dev);
+
if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330) {
min_uv = 3300000;
max_uv = 3300000;
@@ -1011,6 +1052,9 @@ static int msdc_ops_switch_volt(struct mmc_host *mmc, struct mmc_ios *ios)
max_uv = 1800000;
} else {
dev_err(host->dev, "Unsupported signal voltage!\n");
+
+ pm_runtime_mark_last_busy(host->dev);
+ pm_runtime_put_autosuspend(host->dev);
return -EINVAL;
}

@@ -1022,6 +1066,8 @@ static int msdc_ops_switch_volt(struct mmc_host *mmc, struct mmc_ios *ios)
}
}

+ pm_runtime_mark_last_busy(host->dev);
+ pm_runtime_put_autosuspend(host->dev);
return ret;
}

@@ -1186,6 +1232,8 @@ static void msdc_ops_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
int ret;
u32 ddr = 0;

+ pm_runtime_get_sync(host->dev);
+
if (ios->timing == MMC_TIMING_UHS_DDR50)
ddr = 1;

@@ -1230,6 +1278,9 @@ static void msdc_ops_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)

if (host->mclk != ios->clock || host->ddr != ddr)
msdc_set_mclk(host, ddr, ios->clock);
+
+ pm_runtime_mark_last_busy(host->dev);
+ pm_runtime_put_autosuspend(host->dev);
}

static struct mmc_host_ops mt_msdc_ops = {
@@ -1341,6 +1392,11 @@ static int msdc_drv_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, mmc);
clk_prepare(host->src_clk);

+ pm_runtime_enable(host->dev);
+ pm_runtime_get_sync(host->dev);
+ pm_runtime_set_autosuspend_delay(host->dev, MTK_MMC_AUTOSUSPEND_DELAY);
+ pm_runtime_use_autosuspend(host->dev);
+
ret = devm_request_irq(&pdev->dev, (unsigned int) host->irq, msdc_irq,
IRQF_TRIGGER_LOW | IRQF_ONESHOT, pdev->name, host);
if (ret)
@@ -1348,10 +1404,15 @@ static int msdc_drv_probe(struct platform_device *pdev)

ret = mmc_add_host(mmc);
if (ret)
- goto release;
+ goto end;

+ pm_runtime_mark_last_busy(host->dev);
+ pm_runtime_put_autosuspend(host->dev);
return 0;

+end:
+ pm_runtime_put_sync(host->dev);
+ pm_runtime_disable(host->dev);
release:
platform_set_drvdata(pdev, NULL);
msdc_deinit_hw(host);
@@ -1364,6 +1425,7 @@ release_mem:
dma_free_coherent(&pdev->dev,
MAX_BD_NUM * sizeof(struct mt_bdma_desc),
host->dma.bd, host->dma.bd_addr);
+
host_free:
mmc_free_host(mmc);

@@ -1378,10 +1440,14 @@ static int msdc_drv_remove(struct platform_device *pdev)
mmc = platform_get_drvdata(pdev);
host = mmc_priv(mmc);

+ pm_runtime_get_sync(host->dev);
+
platform_set_drvdata(pdev, NULL);
mmc_remove_host(host->mmc);
msdc_deinit_hw(host);

+ pm_runtime_put_sync(host->dev);
+ pm_runtime_disable(host->dev);
dma_free_coherent(&pdev->dev,
MAX_GPD_NUM * sizeof(struct mt_gpdma_desc),
host->dma.gpd, host->dma.gpd_addr);
@@ -1393,6 +1459,31 @@ static int msdc_drv_remove(struct platform_device *pdev)
return 0;
}

+#ifdef CONFIG_PM
+static int msdc_runtime_suspend(struct device *dev)
+{
+ int ret = 0;
+ struct mmc_host *mmc = dev_get_drvdata(dev);
+ struct msdc_host *host = mmc_priv(mmc);
+
+ ret = msdc_gate_clock(host);
+ return ret;
+}
+
+static int msdc_runtime_resume(struct device *dev)
+{
+ struct mmc_host *mmc = dev_get_drvdata(dev);
+ struct msdc_host *host = mmc_priv(mmc);
+
+ msdc_ungate_clock(host);
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops msdc_dev_pm_ops = {
+ SET_RUNTIME_PM_OPS(msdc_runtime_suspend, msdc_runtime_resume, NULL)
+};
+
static const struct of_device_id msdc_of_ids[] = {
{ .compatible = "mediatek,mt8135-mmc", },
{}
@@ -1404,6 +1495,7 @@ static struct platform_driver mt_msdc_driver = {
.driver = {
.name = "mtk-msdc",
.of_match_table = msdc_of_ids,
+ .pm = &msdc_dev_pm_ops,
},
};

--
1.8.1.1.dirty