[PATCH v4 2/4] mmc: sdhci-of-arasan: add phy support for sdhci-of-arasan

From: Shawn Lin
Date: Wed Oct 21 2015 - 23:38:34 EST


This patch adds Generic PHY access for sdhci-of-arasan. Driver
can get PHY handler from dt-binding, and power-on/init the PHY.
Also we add pm ops for PHY here if CONFIG_PM_SLEEP is enabled.
Currently, it's just mandatory for arasan,sdhci-5.1.

Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>

Serise-changes: 4
- remove suspend/resume_phy
- add err handle label for system PM callback
- fix comments of struct sdhci_arasan_data and system PM
callback suggested by Michal

Serise-changes: 3
- remove phy_init/exit for suspend/resume
- adjust phy_int/power_on seq to make code more reasonable
- simplify suspend/resume_phy

Serise-changes: 2
- Keep phy as a mandatory requirement for arasan,sdhci-5.1

---

Changes in v2: None

drivers/mmc/host/sdhci-of-arasan.c | 63 +++++++++++++++++++++++++++++++++++---
1 file changed, 59 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 75379cb..4f30716 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -21,6 +21,7 @@

#include <linux/module.h>
#include <linux/of_device.h>
+#include <linux/phy/phy.h>
#include "sdhci-pltfm.h"

#define SDHCI_ARASAN_CLK_CTRL_OFFSET 0x2c
@@ -32,9 +33,11 @@
/**
* struct sdhci_arasan_data
* @clk_ahb: Pointer to the AHB clock
+ * @phy: Pointer to the generic phy
*/
struct sdhci_arasan_data {
struct clk *clk_ahb;
+ struct phy *phy;
};

static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host)
@@ -72,7 +75,7 @@ static struct sdhci_pltfm_data sdhci_arasan_pdata = {
/**
* sdhci_arasan_suspend - Suspend method for the driver
* @dev: Address of the device structure
- * Returns 0 on success and error value on error
+ * Return: 0 on success and error value on error
*
* Put the device in a low power state.
*/
@@ -88,6 +91,14 @@ static int sdhci_arasan_suspend(struct device *dev)
if (ret)
return ret;

+ if (!IS_ERR(sdhci_arasan->phy)) {
+ ret = phy_power_off(sdhci_arasan->phy);
+ if (ret) {
+ dev_err(dev, "Cannot suspend phy.\n");
+ return ret;
+ }
+ }
+
clk_disable(pltfm_host->clk);
clk_disable(sdhci_arasan->clk_ahb);

@@ -97,7 +108,7 @@ static int sdhci_arasan_suspend(struct device *dev)
/**
* sdhci_arasan_resume - Resume method for the driver
* @dev: Address of the device structure
- * Returns 0 on success and error value on error
+ * Return: 0 on success and error value on error
*
* Resume operation after suspend
*/
@@ -118,11 +129,24 @@ static int sdhci_arasan_resume(struct device *dev)
ret = clk_enable(pltfm_host->clk);
if (ret) {
dev_err(dev, "Cannot enable SD clock.\n");
- clk_disable(sdhci_arasan->clk_ahb);
- return ret;
+ goto err_clk_en;
+ }
+
+ if (!IS_ERR(sdhci_arasan->phy)) {
+ ret = phy_power_on(sdhci_arasan->phy);
+ if (ret) {
+ dev_err(dev, "Cannot resume phy.\n");
+ goto err_phy_power;
+ }
}

return sdhci_resume_host(host);
+
+err_phy_power:
+ clk_disable(pltfm_host->clk);
+err_clk_en:
+ clk_disable(sdhci_arasan->clk_ahb);
+ return ret;
}
#endif /* ! CONFIG_PM_SLEEP */

@@ -188,6 +212,31 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
goto clk_disable_all;
}

+ sdhci_arasan->phy = ERR_PTR(-ENODEV);
+ if (of_device_is_compatible(pdev->dev.of_node,
+ "arasan,sdhci-5.1")) {
+ sdhci_arasan->phy = devm_phy_get(&pdev->dev,
+ "phy_arasan");
+ if (IS_ERR(sdhci_arasan->phy)) {
+ ret = PTR_ERR(sdhci_arasan->phy);
+ dev_err(&pdev->dev, "No phy for arasan,sdhci-5.1.\n");
+ goto clk_disable_all;
+ }
+
+ ret = phy_init(sdhci_arasan->phy);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "phy_init err.\n");
+ goto clk_disable_all;
+ }
+
+ ret = phy_power_on(sdhci_arasan->phy);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "phy_power_on err.\n");
+ phy_exit(sdhci_arasan->phy);
+ goto err_phy_power;
+ }
+ }
+
ret = sdhci_add_host(host);
if (ret)
goto err_pltfm_free;
@@ -196,6 +245,9 @@ static int sdhci_arasan_probe(struct platform_device *pdev)

err_pltfm_free:
sdhci_pltfm_free(pdev);
+err_phy_power:
+ if (!IS_ERR(sdhci_arasan->phy))
+ phy_exit(sdhci_arasan->phy);
clk_disable_all:
clk_disable_unprepare(clk_xin);
clk_dis_ahb:
@@ -210,6 +262,9 @@ static int sdhci_arasan_remove(struct platform_device *pdev)
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;

+ if (!IS_ERR(sdhci_arasan->phy))
+ phy_exit(sdhci_arasan->phy);
+
clk_disable_unprepare(sdhci_arasan->clk_ahb);

return sdhci_pltfm_unregister(pdev);
--
2.3.7


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