MLK-11133: mtd:gpmi: support runtime pm for gpmi nand

support runtime PM on gpmi nand to save the cost to enable/disable clock
in each NAND IO. The driver also claim high-freq bus when resumed.

Signed-off-by: Han Xu <b45815@freescale.com>
(cherry-picked from commit 5b72b3388d1399420f3b49a0ca937ca5792e2d7d)

3 files changed, 69 insertions, 14 deletions

diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
index ab70ce3816e3..1fa46a25e88a 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
@@ -21,6 +21,8 @@
 #include <linux/delay.h>
 #include <linux/clk.h>
 #include <linux/slab.h>
+#include <linux/pm_runtime.h>
+
 
 #include "gpmi-nand.h"
 #include "gpmi-regs.h"
@@ -124,7 +126,7 @@ error:
 	return -ETIMEDOUT;
 }
 
-static int __gpmi_enable_clk(struct gpmi_nand_data *this, bool v)
+int __gpmi_enable_clk(struct gpmi_nand_data *this, bool v)
 {
 	struct clk *clk;
 	int ret;
@@ -151,17 +153,17 @@ err_clk:
 	return ret;
 }
 
-#define gpmi_enable_clk(x) __gpmi_enable_clk(x, true)
-#define gpmi_disable_clk(x) __gpmi_enable_clk(x, false)
-
 int gpmi_init(struct gpmi_nand_data *this)
 {
 	struct resources *r = &this->resources;
 	int ret;
 
-	ret = gpmi_enable_clk(this);
-	if (ret)
+	ret = pm_runtime_get_sync(this->dev);
+	if (ret < 0) {
+		dev_err(this->dev, "Failed to enable clock\n");
 		goto err_out;
+	}
+
 	ret = gpmi_reset_block(r->gpmi_regs, false);
 	if (ret)
 		goto err_out;
@@ -194,7 +196,9 @@ int gpmi_init(struct gpmi_nand_data *this)
 	 */
 	writel(BM_GPMI_CTRL1_DECOUPLE_CS, r->gpmi_regs + HW_GPMI_CTRL1_SET);
 
-	gpmi_disable_clk(this);
+	pm_runtime_mark_last_busy(this->dev);
+	pm_runtime_put_autosuspend(this->dev);
+
 	return 0;
 err_out:
 	return ret;
@@ -268,9 +272,11 @@ int bch_set_geometry(struct gpmi_nand_data *this)
 	page_size     = bch_geo->page_size;
 	gf_len        = bch_geo->gf_len;
 
-	ret = gpmi_enable_clk(this);
-	if (ret)
+	ret = pm_runtime_get_sync(this->dev);
+	if (ret < 0) {
+		dev_err(this->dev, "Failed to enable clock\n");
 		goto err_out;
+	}
 
 	/*
 	* Due to erratum #2847 of the MX23, the BCH cannot be soft reset on this
@@ -310,7 +316,9 @@ int bch_set_geometry(struct gpmi_nand_data *this)
 	writel(BM_BCH_CTRL_COMPLETE_IRQ_EN,
 				r->bch_regs + HW_BCH_CTRL_SET);
 
-	gpmi_disable_clk(this);
+	pm_runtime_mark_last_busy(this->dev);
+	pm_runtime_put_autosuspend(this->dev);
+
 	return 0;
 err_out:
 	return ret;
@@ -1005,9 +1013,9 @@ void gpmi_begin(struct gpmi_nand_data *this)
 	int ret;
 
 	/* Enable the clock. */
-	ret = gpmi_enable_clk(this);
-	if (ret) {
-		dev_err(this->dev, "We failed in enable the clk\n");
+	ret = pm_runtime_get_sync(this->dev);
+	if (ret < 0) {
+		dev_err(this->dev, "Failed to enable clock\n");
 		goto err_out;
 	}
 
@@ -1079,7 +1087,8 @@ err_out:
 
 void gpmi_end(struct gpmi_nand_data *this)
 {
-	gpmi_disable_clk(this);
+	pm_runtime_mark_last_busy(this->dev);
+	pm_runtime_put_autosuspend(this->dev);
 }
 
 /* Clears a BCH interrupt. */
diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
index ef830aeb2780..479efc77fe04 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
@@ -26,6 +26,8 @@
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/of_mtd.h>
+#include <linux/busfreq-imx.h>
+#include <linux/pm_runtime.h>
 #include "gpmi-nand.h"
 #include "bch-regs.h"
 
@@ -34,6 +36,8 @@
 #define GPMI_NAND_BCH_REGS_ADDR_RES_NAME   "bch"
 #define GPMI_NAND_BCH_INTERRUPT_RES_NAME   "bch"
 
+#define GPMI_RPM_TIMEOUT	50 /* ms */
+
 /* add our owner bbt descriptor */
 static uint8_t scan_ff_pattern[] = { 0xff };
 static struct nand_bbt_descr gpmi_bbt_descr = {
@@ -656,6 +660,15 @@ err_clock:
 	return err;
 }
 
+static int init_rpm(struct gpmi_nand_data *this)
+{
+	pm_runtime_enable(this->dev);
+	pm_runtime_set_autosuspend_delay(this->dev, GPMI_RPM_TIMEOUT);
+	pm_runtime_use_autosuspend(this->dev);
+
+	return 0;
+}
+
 static int acquire_resources(struct gpmi_nand_data *this)
 {
 	int ret;
@@ -679,6 +692,7 @@ static int acquire_resources(struct gpmi_nand_data *this)
 	ret = gpmi_get_clks(this);
 	if (ret)
 		goto exit_clock;
+
 	return 0;
 
 exit_clock:
@@ -1856,6 +1870,10 @@ static int gpmi_nand_probe(struct platform_device *pdev)
 	if (ret)
 		goto exit_acquire_resources;
 
+	ret = init_rpm(this);
+	if (ret)
+		goto exit_nfc_init;
+
 	ret = init_hardware(this);
 	if (ret)
 		goto exit_nfc_init;
@@ -1881,6 +1899,7 @@ static int gpmi_nand_remove(struct platform_device *pdev)
 	struct gpmi_nand_data *this = platform_get_drvdata(pdev);
 
 	gpmi_nand_exit(this);
+	pm_runtime_disable(this->dev);
 	release_resources(this);
 	return 0;
 }
@@ -1923,7 +1942,33 @@ static int gpmi_pm_resume(struct device *dev)
 	return 0;
 }
 
+#define gpmi_enable_clk(x) __gpmi_enable_clk(x, true)
+#define gpmi_disable_clk(x) __gpmi_enable_clk(x, false)
+
+int gpmi_runtime_suspend(struct device *dev)
+{
+	struct gpmi_nand_data *this = dev_get_drvdata(dev);
+
+	gpmi_disable_clk(this);
+	release_bus_freq(BUS_FREQ_HIGH);
+	return 0;
+}
+
+int gpmi_runtime_resume(struct device *dev)
+{
+	struct gpmi_nand_data *this = dev_get_drvdata(dev);
+	int ret;
+
+	ret = gpmi_enable_clk(this);
+	if (ret)
+		return ret;
+
+	request_bus_freq(BUS_FREQ_HIGH);
+	return 0;
+}
+
 static const struct dev_pm_ops gpmi_pm_ops = {
+	SET_RUNTIME_PM_OPS(gpmi_runtime_suspend, gpmi_runtime_resume, NULL)
 	SET_SYSTEM_SLEEP_PM_OPS(gpmi_pm_suspend, gpmi_pm_resume)
 };
 
diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.h b/drivers/mtd/nand/gpmi-nand/gpmi-nand.h
index e10502461ed8..5b0e141ff589 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.h
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.h
@@ -277,6 +277,7 @@ extern int start_dma_with_bch_irq(struct gpmi_nand_data *,
 				struct dma_async_tx_descriptor *);
 
 /* GPMI-NAND helper function library */
+extern int __gpmi_enable_clk(struct gpmi_nand_data *, bool v);
 extern int gpmi_init(struct gpmi_nand_data *);
 extern int gpmi_extra_init(struct gpmi_nand_data *);
 extern void gpmi_clear_bch(struct gpmi_nand_data *);