1 files changed, 58 insertions, 20 deletions

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 89a6b46cd319..89977bff76d2 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -256,6 +256,7 @@ struct atmel_spi {
 	void __iomem		*regs;
 	int			irq;
 	struct clk		*clk;
+	struct clk		*gclk;
 	struct platform_device	*pdev;
 	unsigned long		spi_clk;
 
@@ -397,20 +398,10 @@ static void cs_activate(struct atmel_spi *as, struct spi_device *spi)
 		 * on CS1,2,3 needs SPI_CSR0.BITS config as SPI_CSR1,2,3.BITS
 		 */
 		spi_writel(as, CSR0, asd->csr);
-		if (as->caps.has_wdrbt) {
-			spi_writel(as, MR,
-					SPI_BF(PCS, ~(0x01 << chip_select))
-					| SPI_BIT(WDRBT)
-					| SPI_BIT(MODFDIS)
-					| SPI_BIT(MSTR));
-		} else {
-			spi_writel(as, MR,
-					SPI_BF(PCS, ~(0x01 << chip_select))
-					| SPI_BIT(MODFDIS)
-					| SPI_BIT(MSTR));
-		}
 
 		mr = spi_readl(as, MR);
+		mr = SPI_BFINS(PCS, ~(0x01 << chip_select), mr);
+		spi_writel(as, MR, mr);
 
 		/*
 		 * Ensures the clock polarity is valid before we actually
@@ -1490,6 +1481,8 @@ static void atmel_get_caps(struct atmel_spi *as)
 
 static void atmel_spi_init(struct atmel_spi *as)
 {
+	u32 mr = 0;
+
 	spi_writel(as, CR, SPI_BIT(SWRST));
 	spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
 
@@ -1497,12 +1490,17 @@ static void atmel_spi_init(struct atmel_spi *as)
 	if (as->fifo_size)
 		spi_writel(as, CR, SPI_BIT(FIFOEN));
 
-	if (as->caps.has_wdrbt) {
-		spi_writel(as, MR, SPI_BIT(WDRBT) | SPI_BIT(MODFDIS)
-				| SPI_BIT(MSTR));
-	} else {
-		spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS));
-	}
+	/*
+	 * If GCLK is selected as the source clock for the bit rate generation
+	 * Enable the BRSRCCLK/FDIV/DIV32 bit
+	 */
+	if (as->gclk)
+		mr |= SPI_BIT(FDIV);
+
+	if (as->caps.has_wdrbt)
+		mr |= SPI_BIT(WDRBT);
+
+	spi_writel(as, MR, mr | SPI_BIT(MODFDIS) | SPI_BIT(MSTR));
 
 	if (as->use_pdc)
 		spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS));
@@ -1565,6 +1563,11 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	as->phybase = regs->start;
 	as->irq = irq;
 	as->clk = clk;
+	as->gclk = devm_clk_get_optional(&pdev->dev, "spi_gclk");
+	if (IS_ERR(as->gclk)) {
+		ret = PTR_ERR(as->gclk);
+		goto out_unmap_regs;
+	}
 
 	init_completion(&as->xfer_completion);
 
@@ -1625,7 +1628,19 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	if (ret)
 		goto out_free_irq;
 
-	as->spi_clk = clk_get_rate(clk);
+	/*
+	 * In cases where the peripheral clock is higher,the FLEX_SPI_CSRx.SCBR
+	 * exceeds the threshold (SCBR ≤ 255), the GCLK is used as the source clock
+	 * for the SPCK (SPI Serial Clock) bit rate generation
+	 */
+	if (as->gclk) {
+		ret = clk_prepare_enable(as->gclk);
+		if (ret)
+			goto out_disable_clk;
+		as->spi_clk = clk_get_rate(as->gclk);
+	} else {
+		as->spi_clk = clk_get_rate(clk);
+	}
 
 	as->fifo_size = 0;
 	if (!of_property_read_u32(pdev->dev.of_node, "atmel,fifo-size",
@@ -1660,6 +1675,8 @@ out_free_dma:
 
 	spi_writel(as, CR, SPI_BIT(SWRST));
 	spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
+	clk_disable_unprepare(as->gclk);
+out_disable_clk:
 	clk_disable_unprepare(clk);
 out_free_irq:
 out_unmap_regs:
@@ -1695,6 +1712,8 @@ static void atmel_spi_remove(struct platform_device *pdev)
 	spin_unlock_irq(&as->lock);
 
 	clk_disable_unprepare(as->clk);
+	if (as->gclk)
+		clk_disable_unprepare(as->gclk);
 
 	pm_runtime_put_noidle(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
@@ -1706,6 +1725,8 @@ static int atmel_spi_runtime_suspend(struct device *dev)
 	struct atmel_spi *as = spi_controller_get_devdata(host);
 
 	clk_disable_unprepare(as->clk);
+	if (as->gclk)
+		clk_disable_unprepare(as->gclk);
 	pinctrl_pm_select_sleep_state(dev);
 
 	return 0;
@@ -1715,10 +1736,20 @@ static int atmel_spi_runtime_resume(struct device *dev)
 {
 	struct spi_controller *host = dev_get_drvdata(dev);
 	struct atmel_spi *as = spi_controller_get_devdata(host);
+	int ret;
 
 	pinctrl_pm_select_default_state(dev);
 
-	return clk_prepare_enable(as->clk);
+	ret = clk_prepare_enable(as->clk);
+	if (ret)
+		return ret;
+	if (as->gclk) {
+		ret = clk_prepare_enable(as->gclk);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
 }
 
 static int atmel_spi_suspend(struct device *dev)
@@ -1746,10 +1777,17 @@ static int atmel_spi_resume(struct device *dev)
 	ret = clk_prepare_enable(as->clk);
 	if (ret)
 		return ret;
+	if (as->gclk) {
+		ret = clk_prepare_enable(as->gclk);
+		if (ret)
+			return ret;
+	}
 
 	atmel_spi_init(as);
 
 	clk_disable_unprepare(as->clk);
+	if (as->gclk)
+		clk_disable_unprepare(as->gclk);
 
 	if (!pm_runtime_suspended(dev)) {
 		ret = atmel_spi_runtime_resume(dev);