1 files changed, 56 insertions, 25 deletions

diff --git a/drivers/mtd/spi-nor/fsl-quadspi.c b/drivers/mtd/spi-nor/fsl-quadspi.c
index a5db7ad8fc20..8a69b2caa792 100644
--- a/drivers/mtd/spi-nor/fsl-quadspi.c
+++ b/drivers/mtd/spi-nor/fsl-quadspi.c
@@ -655,6 +655,32 @@ static void fsl_qspi_init_abh_read(struct fsl_qspi *q)
 		q->iobase + QUADSPI_BFGENCR);
 }
 
+/* This function was used to prepare and enable QSPI clock */
+static int fsl_qspi_clk_prep_enable(struct fsl_qspi *q)
+{
+	int ret;
+
+	ret = clk_prepare_enable(q->clk_en);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(q->clk);
+	if (ret) {
+		clk_disable_unprepare(q->clk_en);
+		return ret;
+	}
+
+	return 0;
+}
+
+/* This function was used to disable and unprepare QSPI clock */
+static void fsl_qspi_clk_disable_unprep(struct fsl_qspi *q)
+{
+	clk_disable_unprepare(q->clk);
+	clk_disable_unprepare(q->clk_en);
+
+}
+
 /* We use this function to do some basic init for spi_nor_scan(). */
 static int fsl_qspi_nor_setup(struct fsl_qspi *q)
 {
@@ -662,11 +688,18 @@ static int fsl_qspi_nor_setup(struct fsl_qspi *q)
 	u32 reg;
 	int ret;
 
-	/* the default frequency, we will change it in the future.*/
+	/* disable and unprepare clock to avoid glitch pass to controller */
+	fsl_qspi_clk_disable_unprep(q);
+
+	/* the default frequency, we will change it in the future. */
 	ret = clk_set_rate(q->clk, 66000000);
 	if (ret)
 		return ret;
 
+	ret = fsl_qspi_clk_prep_enable(q);
+	if (ret)
+		return ret;
+
 	/* Init the LUT table. */
 	fsl_qspi_init_lut(q);
 
@@ -698,10 +731,17 @@ static int fsl_qspi_nor_setup_last(struct fsl_qspi *q)
 	if (needs_4x_clock(q))
 		rate *= 4;
 
+	/* disable and unprepare clock to avoid glitch pass to controller */
+	fsl_qspi_clk_disable_unprep(q);
+
 	ret = clk_set_rate(q->clk, rate);
 	if (ret)
 		return ret;
 
+	ret = fsl_qspi_clk_prep_enable(q);
+	if (ret)
+		return ret;
+
 	/* Init the LUT table again. */
 	fsl_qspi_init_lut(q);
 
@@ -844,22 +884,16 @@ static int fsl_qspi_prep(struct spi_nor *nor, enum spi_nor_ops ops)
 	int ret;
 
 	mutex_lock(&q->lock);
-	ret = clk_enable(q->clk_en);
-	if (ret)
-		goto err_mutex;
 
-	ret = clk_enable(q->clk);
+	ret = fsl_qspi_clk_prep_enable(q);
 	if (ret)
-		goto err_clk;
+		goto err_mutex;
 
 	fsl_qspi_set_base_addr(q, nor);
 	return 0;
 
-err_clk:
-	clk_disable(q->clk_en);
 err_mutex:
 	mutex_unlock(&q->lock);
-
 	return ret;
 }
 
@@ -867,8 +901,7 @@ static void fsl_qspi_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
 {
 	struct fsl_qspi *q = nor->priv;
 
-	clk_disable(q->clk);
-	clk_disable(q->clk_en);
+	fsl_qspi_clk_disable_unprep(q);
 	mutex_unlock(&q->lock);
 }
 
@@ -918,15 +951,9 @@ static int fsl_qspi_probe(struct platform_device *pdev)
 	if (IS_ERR(q->clk))
 		return PTR_ERR(q->clk);
 
-	ret = clk_prepare_enable(q->clk_en);
+	ret = fsl_qspi_clk_prep_enable(q);
 	if (ret) {
-		dev_err(dev, "cannot enable the qspi_en clock: %d\n", ret);
-		return ret;
-	}
-
-	ret = clk_prepare_enable(q->clk);
-	if (ret) {
-		dev_err(dev, "cannot enable the qspi clock: %d\n", ret);
+		dev_err(dev, "can not enable the clock\n");
 		goto clk_failed;
 	}
 
@@ -1032,8 +1059,7 @@ static int fsl_qspi_probe(struct platform_device *pdev)
 	if (ret)
 		goto last_init_failed;
 
-	clk_disable(q->clk);
-	clk_disable(q->clk_en);
+	fsl_qspi_clk_disable_unprep(q);
 	return 0;
 
 last_init_failed:
@@ -1046,9 +1072,9 @@ last_init_failed:
 mutex_failed:
 	mutex_destroy(&q->lock);
 irq_failed:
-	clk_disable_unprepare(q->clk);
+	fsl_qspi_clk_disable_unprep(q);
 clk_failed:
-	clk_disable_unprepare(q->clk_en);
+	dev_err(dev, "Freescale QuadSPI probe failed\n");
 	return ret;
 }
 
@@ -1069,8 +1095,6 @@ static int fsl_qspi_remove(struct platform_device *pdev)
 	writel(0x0, q->iobase + QUADSPI_RSER);
 
 	mutex_destroy(&q->lock);
-	clk_unprepare(q->clk);
-	clk_unprepare(q->clk_en);
 
 	if (q->ahb_addr)
 		iounmap(q->ahb_addr);
@@ -1085,12 +1109,19 @@ static int fsl_qspi_suspend(struct platform_device *pdev, pm_message_t state)
 
 static int fsl_qspi_resume(struct platform_device *pdev)
 {
+	int ret;
 	struct fsl_qspi *q = platform_get_drvdata(pdev);
 
+	ret = fsl_qspi_clk_prep_enable(q);
+	if (ret)
+		return ret;
+
 	fsl_qspi_nor_setup(q);
 	fsl_qspi_set_map_addr(q);
 	fsl_qspi_nor_setup_last(q);
 
+	fsl_qspi_clk_disable_unprep(q);
+
 	return 0;
 }