These changes are the raw update to linux-4.4.6-rt14. Kernel sources

are taken from kernel.org, and rt patch from the rt wiki download page.

During the rebasing, the following patch collided:

Force tick interrupt and get rid of softirq magic(I70131fb85).

Collisions have been removed because its logic was found on the
source already.

Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

1 files changed, 48 insertions, 24 deletions

diff --git a/kernel/drivers/spi/spi-davinci.c b/kernel/drivers/spi/spi-davinci.c
index 5e991065f..7d3af3eac 100644
--- a/kernel/drivers/spi/spi-davinci.c
+++ b/kernel/drivers/spi/spi-davinci.c
@@ -139,6 +139,8 @@ struct davinci_spi {
 	u32			(*get_tx)(struct davinci_spi *);
 
 	u8			*bytes_per_word;
+
+	u8			prescaler_limit;
 };
 
 static struct davinci_spi_config davinci_spi_default_cfg;
@@ -213,18 +215,10 @@ static void davinci_spi_chipselect(struct spi_device *spi, int value)
 	struct davinci_spi_config *spicfg = spi->controller_data;
 	u8 chip_sel = spi->chip_select;
 	u16 spidat1 = CS_DEFAULT;
-	bool gpio_chipsel = false;
-	int gpio;
 
 	dspi = spi_master_get_devdata(spi->master);
 	pdata = &dspi->pdata;
 
-	if (spi->cs_gpio >= 0) {
-		/* SPI core parse and update master->cs_gpio */
-		gpio_chipsel = true;
-		gpio = spi->cs_gpio;
-	}
-
 	/* program delay transfers if tx_delay is non zero */
 	if (spicfg->wdelay)
 		spidat1 |= SPIDAT1_WDEL;
@@ -233,11 +227,12 @@ static void davinci_spi_chipselect(struct spi_device *spi, int value)
 	 * Board specific chip select logic decides the polarity and cs
 	 * line for the controller
 	 */
-	if (gpio_chipsel) {
+	if (spi->cs_gpio >= 0) {
 		if (value == BITBANG_CS_ACTIVE)
-			gpio_set_value(gpio, spi->mode & SPI_CS_HIGH);
+			gpio_set_value(spi->cs_gpio, spi->mode & SPI_CS_HIGH);
 		else
-			gpio_set_value(gpio, !(spi->mode & SPI_CS_HIGH));
+			gpio_set_value(spi->cs_gpio,
+				!(spi->mode & SPI_CS_HIGH));
 	} else {
 		if (value == BITBANG_CS_ACTIVE) {
 			spidat1 |= SPIDAT1_CSHOLD_MASK;
@@ -255,7 +250,7 @@ static void davinci_spi_chipselect(struct spi_device *spi, int value)
  * This function calculates the prescale value that generates a clock rate
  * less than or equal to the specified maximum.
  *
- * Returns: calculated prescale - 1 for easy programming into SPI registers
+ * Returns: calculated prescale value for easy programming into SPI registers
  * or negative error number if valid prescalar cannot be updated.
  */
 static inline int davinci_spi_get_prescale(struct davinci_spi *dspi,
@@ -263,12 +258,13 @@ static inline int davinci_spi_get_prescale(struct davinci_spi *dspi,
 {
 	int ret;
 
-	ret = DIV_ROUND_UP(clk_get_rate(dspi->clk), max_speed_hz);
+	/* Subtract 1 to match what will be programmed into SPI register. */
+	ret = DIV_ROUND_UP(clk_get_rate(dspi->clk), max_speed_hz) - 1;
 
-	if (ret < 3 || ret > 256)
+	if (ret < dspi->prescaler_limit || ret > 255)
 		return -EINVAL;
 
-	return ret - 1;
+	return ret;
 }
 
 /**
@@ -832,13 +828,40 @@ rx_dma_failed:
 }
 
 #if defined(CONFIG_OF)
+
+/* OF SPI data structure */
+struct davinci_spi_of_data {
+	u8	version;
+	u8	prescaler_limit;
+};
+
+static const struct davinci_spi_of_data dm6441_spi_data = {
+	.version = SPI_VERSION_1,
+	.prescaler_limit = 2,
+};
+
+static const struct davinci_spi_of_data da830_spi_data = {
+	.version = SPI_VERSION_2,
+	.prescaler_limit = 2,
+};
+
+static const struct davinci_spi_of_data keystone_spi_data = {
+	.version = SPI_VERSION_1,
+	.prescaler_limit = 0,
+};
+
 static const struct of_device_id davinci_spi_of_match[] = {
 	{
 		.compatible = "ti,dm6441-spi",
+		.data = &dm6441_spi_data,
 	},
 	{
 		.compatible = "ti,da830-spi",
-		.data = (void *)SPI_VERSION_2,
+		.data = &da830_spi_data,
+	},
+	{
+		.compatible = "ti,keystone-spi",
+		.data = &keystone_spi_data,
 	},
 	{ },
 };
@@ -857,21 +880,21 @@ static int spi_davinci_get_pdata(struct platform_device *pdev,
 			struct davinci_spi *dspi)
 {
 	struct device_node *node = pdev->dev.of_node;
+	struct davinci_spi_of_data *spi_data;
 	struct davinci_spi_platform_data *pdata;
 	unsigned int num_cs, intr_line = 0;
 	const struct of_device_id *match;
 
 	pdata = &dspi->pdata;
 
-	pdata->version = SPI_VERSION_1;
 	match = of_match_device(davinci_spi_of_match, &pdev->dev);
 	if (!match)
 		return -ENODEV;
 
-	/* match data has the SPI version number for SPI_VERSION_2 */
-	if (match->data == (void *)SPI_VERSION_2)
-		pdata->version = SPI_VERSION_2;
+	spi_data = (struct davinci_spi_of_data *)match->data;
 
+	pdata->version = spi_data->version;
+	pdata->prescaler_limit = spi_data->prescaler_limit;
 	/*
 	 * default num_cs is 1 and all chipsel are internal to the chip
 	 * indicated by chip_sel being NULL or cs_gpios being NULL or
@@ -962,11 +985,12 @@ static int davinci_spi_probe(struct platform_device *pdev)
 		goto free_master;
 	}
 
-	dspi->irq = platform_get_irq(pdev, 0);
-	if (dspi->irq <= 0) {
+	ret = platform_get_irq(pdev, 0);
+	if (ret == 0)
 		ret = -EINVAL;
+	if (ret < 0)
 		goto free_master;
-	}
+	dspi->irq = ret;
 
 	ret = devm_request_threaded_irq(&pdev->dev, dspi->irq, davinci_spi_irq,
 				dummy_thread_fn, 0, dev_name(&pdev->dev), dspi);
@@ -991,7 +1015,7 @@ static int davinci_spi_probe(struct platform_device *pdev)
 
 	dspi->bitbang.chipselect = davinci_spi_chipselect;
 	dspi->bitbang.setup_transfer = davinci_spi_setup_transfer;
-
+	dspi->prescaler_limit = pdata->prescaler_limit;
 	dspi->version = pdata->version;
 
 	dspi->bitbang.flags = SPI_NO_CS | SPI_LSB_FIRST | SPI_LOOP;