spi: Fixes for v4.19

Quite a few fixes for the Renesas drivers in here, plus a fix for the
 Tegra driver and some documentation fixes for the recently added spi-mem
 code.  The Tegra fix is relatively large but fairly straightforward and
 mechanical, it runs on probe so it's been reasonably well covered in
 -next testing.
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Merge tag 'spi-fix-v4.19-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Mark writes:
  "spi: Fixes for v4.19

   Quite a few fixes for the Renesas drivers in here, plus a fix for the
   Tegra driver and some documentation fixes for the recently added
   spi-mem code.  The Tegra fix is relatively large but fairly
   straightforward and mechanical, it runs on probe so it's been
   reasonably well covered in -next testing."

* tag 'spi-fix-v4.19-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: spi-mem: Move the DMA-able constraint doc to the kerneldoc header
  spi: spi-mem: Add missing description for data.nbytes field
  spi: rspi: Fix interrupted DMA transfers
  spi: rspi: Fix invalid SPI use during system suspend
  spi: sh-msiof: Fix handling of write value for SISTR register
  spi: sh-msiof: Fix invalid SPI use during system suspend
  spi: gpio: Fix copy-and-paste error
  spi: tegra20-slink: explicitly enable/disable clock

drivers/spi/spi-gpio.c

@@ -300,8 +300,8 @@ static int spi_gpio_request(struct device *dev,
 		*mflags |= SPI_MASTER_NO_RX;
 
 	spi_gpio->sck = devm_gpiod_get(dev, "sck", GPIOD_OUT_LOW);
-	if (IS_ERR(spi_gpio->mosi))
+	if (IS_ERR(spi_gpio->sck))
-		return PTR_ERR(spi_gpio->mosi);
+		return PTR_ERR(spi_gpio->sck);
 
 	for (i = 0; i < num_chipselects; i++) {
 		spi_gpio->cs_gpios[i] = devm_gpiod_get_index(dev, "cs",

drivers/spi/spi-rspi.c

@@ -598,11 +598,13 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
 
 	ret = wait_event_interruptible_timeout(rspi->wait,
 					       rspi->dma_callbacked, HZ);
-	if (ret > 0 && rspi->dma_callbacked)
+	if (ret > 0 && rspi->dma_callbacked) {
 		ret = 0;
-	else if (!ret) {
+	} else {
-		dev_err(&rspi->master->dev, "DMA timeout\n");
+		if (!ret) {
-		ret = -ETIMEDOUT;
+			dev_err(&rspi->master->dev, "DMA timeout\n");
+			ret = -ETIMEDOUT;
+		}
 		if (tx)
 			dmaengine_terminate_all(rspi->master->dma_tx);
 		if (rx)
@@ -1350,12 +1352,36 @@ static const struct platform_device_id spi_driver_ids[] = {
 
 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
 
+#ifdef CONFIG_PM_SLEEP
+static int rspi_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct rspi_data *rspi = platform_get_drvdata(pdev);
+
+	return spi_master_suspend(rspi->master);
+}
+
+static int rspi_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct rspi_data *rspi = platform_get_drvdata(pdev);
+
+	return spi_master_resume(rspi->master);
+}
+
+static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume);
+#define DEV_PM_OPS	&rspi_pm_ops
+#else
+#define DEV_PM_OPS	NULL
+#endif /* CONFIG_PM_SLEEP */
+
 static struct platform_driver rspi_driver = {
 	.probe =	rspi_probe,
 	.remove =	rspi_remove,
 	.id_table =	spi_driver_ids,
 	.driver		= {
 		.name = "renesas_spi",
+		.pm = DEV_PM_OPS,
 		.of_match_table = of_match_ptr(rspi_of_match),
 	},
 };

drivers/spi/spi-sh-msiof.c

@@ -397,7 +397,8 @@ static void sh_msiof_spi_set_mode_regs(struct sh_msiof_spi_priv *p,
 
 static void sh_msiof_reset_str(struct sh_msiof_spi_priv *p)
 {
-	sh_msiof_write(p, STR, sh_msiof_read(p, STR));
+	sh_msiof_write(p, STR,
+		       sh_msiof_read(p, STR) & ~(STR_TDREQ | STR_RDREQ));
 }
 
 static void sh_msiof_spi_write_fifo_8(struct sh_msiof_spi_priv *p,
@@ -1426,12 +1427,37 @@ static const struct platform_device_id spi_driver_ids[] = {
 };
 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
 
+#ifdef CONFIG_PM_SLEEP
+static int sh_msiof_spi_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
+
+	return spi_master_suspend(p->master);
+}
+
+static int sh_msiof_spi_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
+
+	return spi_master_resume(p->master);
+}
+
+static SIMPLE_DEV_PM_OPS(sh_msiof_spi_pm_ops, sh_msiof_spi_suspend,
+			 sh_msiof_spi_resume);
+#define DEV_PM_OPS	&sh_msiof_spi_pm_ops
+#else
+#define DEV_PM_OPS	NULL
+#endif /* CONFIG_PM_SLEEP */
+
 static struct platform_driver sh_msiof_spi_drv = {
 	.probe		= sh_msiof_spi_probe,
 	.remove		= sh_msiof_spi_remove,
 	.id_table	= spi_driver_ids,
 	.driver		= {
 		.name		= "spi_sh_msiof",
+		.pm		= DEV_PM_OPS,
 		.of_match_table = of_match_ptr(sh_msiof_match),
 	},
 };

drivers/spi/spi-tegra20-slink.c

@@ -1063,6 +1063,24 @@ static int tegra_slink_probe(struct platform_device *pdev)
 		goto exit_free_master;
 	}
 
+	/* disabled clock may cause interrupt storm upon request */
+	tspi->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(tspi->clk)) {
+		ret = PTR_ERR(tspi->clk);
+		dev_err(&pdev->dev, "Can not get clock %d\n", ret);
+		goto exit_free_master;
+	}
+	ret = clk_prepare(tspi->clk);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Clock prepare failed %d\n", ret);
+		goto exit_free_master;
+	}
+	ret = clk_enable(tspi->clk);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Clock enable failed %d\n", ret);
+		goto exit_free_master;
+	}
+
 	spi_irq = platform_get_irq(pdev, 0);
 	tspi->irq = spi_irq;
 	ret = request_threaded_irq(tspi->irq, tegra_slink_isr,
@@ -1071,14 +1089,7 @@ static int tegra_slink_probe(struct platform_device *pdev)
 	if (ret < 0) {
 		dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n",
 					tspi->irq);
-		goto exit_free_master;
+		goto exit_clk_disable;
-	}
-
-	tspi->clk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(tspi->clk)) {
-		dev_err(&pdev->dev, "can not get clock\n");
-		ret = PTR_ERR(tspi->clk);
-		goto exit_free_irq;
 	}
 
 	tspi->rst = devm_reset_control_get_exclusive(&pdev->dev, "spi");
@@ -1138,6 +1149,8 @@ exit_rx_dma_free:
 	tegra_slink_deinit_dma_param(tspi, true);
 exit_free_irq:
 	free_irq(spi_irq, tspi);
+exit_clk_disable:
+	clk_disable(tspi->clk);
 exit_free_master:
 	spi_master_put(master);
 	return ret;
@@ -1150,6 +1163,8 @@ static int tegra_slink_remove(struct platform_device *pdev)
 
 	free_irq(tspi->irq, tspi);
 
+	clk_disable(tspi->clk);
+
 	if (tspi->tx_dma_chan)
 		tegra_slink_deinit_dma_param(tspi, false);
 

include/linux/spi/spi-mem.h

@@ -81,8 +81,10 @@ enum spi_mem_data_dir {
  * @dummy.buswidth: number of IO lanes used to transmit the dummy bytes
  * @data.buswidth: number of IO lanes used to send/receive the data
  * @data.dir: direction of the transfer
- * @data.buf.in: input buffer
+ * @data.nbytes: number of data bytes to send/receive. Can be zero if the
- * @data.buf.out: output buffer
+ *		 operation does not involve transferring data
+ * @data.buf.in: input buffer (must be DMA-able)
+ * @data.buf.out: output buffer (must be DMA-able)
  */
 struct spi_mem_op {
 	struct {
@@ -105,7 +107,6 @@ struct spi_mem_op {
 		u8 buswidth;
 		enum spi_mem_data_dir dir;
 		unsigned int nbytes;
-		/* buf.{in,out} must be DMA-able. */
 		union {
 			void *in;
 			const void *out;