[PATCH RFC v2] mmc: sdhci_am654: Add support for PM suspend/resume
From: Aswath Govindraju
Date: Fri Apr 08 2022 - 08:43:56 EST
Add support for suspend/resume and pm_runtime resume/suspend.
Signed-off-by: Aswath Govindraju <a-govindraju@xxxxxx>
---
Changes since v1:
- Removed System pm calls and used force_runtime_pm calls instead
- Added error handling at required places
- Added pm_runtime_sync call in the sdhci_am654_remove function
- Replaced pm_runtime_*_sync calls in probe with noidle and noresume
calls
- Used MACRO SET_RUNTIME_PM_OPS to avoid build errors when CONFIG_PM
is disabled
drivers/mmc/host/sdhci_am654.c | 146 +++++++++++++++++++++++++++++----
1 file changed, 132 insertions(+), 14 deletions(-)
diff --git a/drivers/mmc/host/sdhci_am654.c b/drivers/mmc/host/sdhci_am654.c
index e54fe24d47e7..131b2b9ae0e7 100644
--- a/drivers/mmc/host/sdhci_am654.c
+++ b/drivers/mmc/host/sdhci_am654.c
@@ -84,6 +84,7 @@
#define DRIVER_STRENGTH_40_OHM 0x4
#define CLOCK_TOO_SLOW_HZ 50000000
+#define SDHCI_AM654_AUTOSUSPEND_DELAY 100
/* Command Queue Host Controller Interface Base address */
#define SDHCI_AM654_CQE_BASE_ADDR 0x200
@@ -791,16 +792,10 @@ static int sdhci_am654_probe(struct platform_device *pdev)
pltfm_host->clk = clk_xin;
- /* Clocks are enabled using pm_runtime */
- pm_runtime_enable(dev);
- ret = pm_runtime_resume_and_get(dev);
- if (ret)
- goto pm_runtime_disable;
-
base = devm_platform_ioremap_resource(pdev, 1);
if (IS_ERR(base)) {
ret = PTR_ERR(base);
- goto pm_runtime_put;
+ goto err_pltfm_free;
}
sdhci_am654->base = devm_regmap_init_mmio(dev, base,
@@ -808,31 +803,47 @@ static int sdhci_am654_probe(struct platform_device *pdev)
if (IS_ERR(sdhci_am654->base)) {
dev_err(dev, "Failed to initialize regmap\n");
ret = PTR_ERR(sdhci_am654->base);
- goto pm_runtime_put;
+ goto err_pltfm_free;
}
ret = sdhci_am654_get_of_property(pdev, sdhci_am654);
if (ret)
- goto pm_runtime_put;
+ goto err_pltfm_free;
ret = mmc_of_parse(host->mmc);
if (ret) {
dev_err(dev, "parsing dt failed (%d)\n", ret);
- goto pm_runtime_put;
+ goto err_pltfm_free;
}
host->mmc_host_ops.execute_tuning = sdhci_am654_execute_tuning;
+ pm_runtime_get_noresume(dev);
+ ret = pm_runtime_set_active(dev);
+ if (ret)
+ goto pm_put;
+ pm_runtime_enable(dev);
+ ret = clk_prepare_enable(pltfm_host->clk);
+ if (ret)
+ goto pm_disable;
+
ret = sdhci_am654_init(host);
if (ret)
- goto pm_runtime_put;
+ goto clk_disable;
+ /* Setting up autosuspend */
+ pm_runtime_set_autosuspend_delay(dev, SDHCI_AM654_AUTOSUSPEND_DELAY);
+ pm_runtime_use_autosuspend(dev);
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
return 0;
-pm_runtime_put:
- pm_runtime_put_sync(dev);
-pm_runtime_disable:
+clk_disable:
+ clk_disable_unprepare(pltfm_host->clk);
+pm_disable:
pm_runtime_disable(dev);
+pm_put:
+ pm_runtime_put_noidle(dev);
err_pltfm_free:
sdhci_pltfm_free(pdev);
return ret;
@@ -841,23 +852,130 @@ static int sdhci_am654_probe(struct platform_device *pdev)
static int sdhci_am654_remove(struct platform_device *pdev)
{
struct sdhci_host *host = platform_get_drvdata(pdev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
int ret;
+ ret = pm_runtime_get_sync(&pdev->dev);
+ if (ret < 0)
+ return ret;
+
sdhci_remove_host(host, true);
ret = pm_runtime_put_sync(&pdev->dev);
if (ret < 0)
return ret;
+ clk_disable_unprepare(pltfm_host->clk);
pm_runtime_disable(&pdev->dev);
sdhci_pltfm_free(pdev);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int sdhci_am654_restore(struct sdhci_host *host)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
+ u32 ctl_cfg_2 = 0;
+ u32 val;
+ int ret;
+
+ if (sdhci_am654->flags & DLL_CALIB) {
+ regmap_read(sdhci_am654->base, PHY_STAT1, &val);
+ if (~val & CALDONE_MASK) {
+ /* Calibrate IO lines */
+ regmap_update_bits(sdhci_am654->base, PHY_CTRL1,
+ PDB_MASK, PDB_MASK);
+ ret = regmap_read_poll_timeout(sdhci_am654->base,
+ PHY_STAT1, val,
+ val & CALDONE_MASK,
+ 1, 20);
+ if (ret)
+ return ret;
+ }
+ }
+
+ /* Enable pins by setting IO mux to 0 */
+ if (sdhci_am654->flags & IOMUX_PRESENT)
+ regmap_update_bits(sdhci_am654->base, PHY_CTRL1,
+ IOMUX_ENABLE_MASK, 0);
+ /* Set slot type based on SD or eMMC */
+ if (host->mmc->caps & MMC_CAP_NONREMOVABLE)
+ ctl_cfg_2 = SLOTTYPE_EMBEDDED;
+
+ regmap_update_bits(sdhci_am654->base, CTL_CFG_2, SLOTTYPE_MASK,
+ ctl_cfg_2);
+
+ regmap_read(sdhci_am654->base, CTL_CFG_3, &val);
+ if (~val & TUNINGFORSDR50_MASK)
+ /* Enable tuning for SDR50 */
+ regmap_update_bits(sdhci_am654->base, CTL_CFG_3, TUNINGFORSDR50_MASK,
+ TUNINGFORSDR50_MASK);
+
+ return 0;
+}
+
+static int sdhci_am654_runtime_suspend(struct device *dev)
+{
+ struct sdhci_host *host = dev_get_drvdata(dev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ int ret;
+
+ if (host->tuning_mode != SDHCI_TUNING_MODE_3)
+ mmc_retune_needed(host->mmc);
+
+ ret = cqhci_suspend(host->mmc);
+ if (ret)
+ return ret;
+
+ ret = sdhci_runtime_suspend_host(host);
+ if (ret)
+ return ret;
+
+ /* disable the clock */
+ clk_disable_unprepare(pltfm_host->clk);
return 0;
}
+static int sdhci_am654_runtime_resume(struct device *dev)
+{
+ struct sdhci_host *host = dev_get_drvdata(dev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ int ret;
+
+ /* Enable the clock */
+ ret = clk_prepare_enable(pltfm_host->clk);
+ if (ret)
+ return ret;
+
+ ret = sdhci_am654_restore(host);
+ if (ret)
+ return ret;
+
+ ret = sdhci_runtime_resume_host(host, 0);
+ if (ret)
+ return ret;
+
+ ret = cqhci_resume(host->mmc);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops sdhci_am654_dev_pm_ops = {
+ SET_RUNTIME_PM_OPS(sdhci_am654_runtime_suspend,
+ sdhci_am654_runtime_resume, NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+};
+
static struct platform_driver sdhci_am654_driver = {
.driver = {
.name = "sdhci-am654",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ .pm = &sdhci_am654_dev_pm_ops,
.of_match_table = sdhci_am654_of_match,
},
.probe = sdhci_am654_probe,
--
2.17.1