Merge remote-tracking branches 'spi/fix/atmel', 'spi/fix/mvbeu' and 'spi/fix/spidev' into spi-linus

drivers/spi/spi-atmel.c

@@ -24,6 +24,7 @@
 
 #include <linux/io.h>
 #include <linux/gpio.h>
+#include <linux/of_gpio.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/pm_runtime.h>
 
@@ -295,6 +296,7 @@ struct atmel_spi {
 	int			irq;
 	struct clk		*clk;
 	struct platform_device	*pdev;
+	unsigned long		spi_clk;
 
 	struct spi_transfer	*current_transfer;
 	int			current_remaining_bytes;
@@ -864,7 +866,7 @@ static int atmel_spi_set_xfer_speed(struct atmel_spi *as,
 	unsigned long		bus_hz;
 
 	/* v1 chips start out at half the peripheral bus speed. */
-	bus_hz = clk_get_rate(as->clk);
+	bus_hz = as->spi_clk;
 	if (!atmel_spi_is_v2(as))
 		bus_hz /= 2;
 
@@ -1204,7 +1206,6 @@ static int atmel_spi_setup(struct spi_device *spi)
 	u32			csr;
 	unsigned int		bits = spi->bits_per_word;
 	unsigned int		npcs_pin;
-	int			ret;
 
 	as = spi_master_get_devdata(spi->master);
 
@@ -1247,16 +1248,9 @@ static int atmel_spi_setup(struct spi_device *spi)
 		if (!asd)
 			return -ENOMEM;
 
-		if (as->use_cs_gpios) {
-			ret = gpio_request(npcs_pin, dev_name(&spi->dev));
-			if (ret) {
-				kfree(asd);
-				return ret;
-			}
-
+		if (as->use_cs_gpios)
 			gpio_direction_output(npcs_pin,
 					      !(spi->mode & SPI_CS_HIGH));
-		}
 
 		asd->npcs_pin = npcs_pin;
 		spi->controller_state = asd;
@@ -1471,13 +1465,11 @@ static int atmel_spi_transfer_one_message(struct spi_master *master,
 static void atmel_spi_cleanup(struct spi_device *spi)
 {
 	struct atmel_spi_device	*asd = spi->controller_state;
-	unsigned		gpio = (unsigned long) spi->controller_data;
 
 	if (!asd)
 		return;
 
 	spi->controller_state = NULL;
-	gpio_free(gpio);
 	kfree(asd);
 }
 
@@ -1499,6 +1491,39 @@ static void atmel_get_caps(struct atmel_spi *as)
 }
 
 /*-------------------------------------------------------------------------*/
+static int atmel_spi_gpio_cs(struct platform_device *pdev)
+{
+	struct spi_master	*master = platform_get_drvdata(pdev);
+	struct atmel_spi	*as = spi_master_get_devdata(master);
+	struct device_node	*np = master->dev.of_node;
+	int			i;
+	int			ret = 0;
+	int			nb = 0;
+
+	if (!as->use_cs_gpios)
+		return 0;
+
+	if (!np)
+		return 0;
+
+	nb = of_gpio_named_count(np, "cs-gpios");
+	for (i = 0; i < nb; i++) {
+		int cs_gpio = of_get_named_gpio(pdev->dev.of_node,
+						"cs-gpios", i);
+
+			if (cs_gpio == -EPROBE_DEFER)
+				return cs_gpio;
+
+			if (gpio_is_valid(cs_gpio)) {
+				ret = devm_gpio_request(&pdev->dev, cs_gpio,
+							dev_name(&pdev->dev));
+				if (ret)
+					return ret;
+			}
+	}
+
+	return 0;
+}
 
 static int atmel_spi_probe(struct platform_device *pdev)
 {
@@ -1577,6 +1602,10 @@ static int atmel_spi_probe(struct platform_device *pdev)
 		master->num_chipselect = 4;
 	}
 
+	ret = atmel_spi_gpio_cs(pdev);
+	if (ret)
+		goto out_unmap_regs;
+
 	as->use_dma = false;
 	as->use_pdc = false;
 	if (as->caps.has_dma_support) {
@@ -1606,6 +1635,9 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	ret = clk_prepare_enable(clk);
 	if (ret)
 		goto out_free_irq;
+
+	as->spi_clk = clk_get_rate(clk);
+
 	spi_writel(as, CR, SPI_BIT(SWRST));
 	spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
 	if (as->caps.has_wdrbt) {

drivers/spi/spi-orion.c

@@ -138,37 +138,62 @@ static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed)
 	tclk_hz = clk_get_rate(orion_spi->clk);
 
 	if (devdata->typ == ARMADA_SPI) {
-		unsigned int clk, spr, sppr, sppr2, err;
-		unsigned int best_spr, best_sppr, best_err;
-
-		best_err = speed;
-		best_spr = 0;
-		best_sppr = 0;
-
-		/* Iterate over the valid range looking for best fit */
-		for (sppr = 0; sppr < 8; sppr++) {
-			sppr2 = 0x1 << sppr;
-
-			spr = tclk_hz / sppr2;
-			spr = DIV_ROUND_UP(spr, speed);
-			if ((spr == 0) || (spr > 15))
-				continue;
-
-			clk = tclk_hz / (spr * sppr2);
-			err = speed - clk;
-
-			if (err < best_err) {
-				best_spr = spr;
-				best_sppr = sppr;
-				best_err = err;
-			}
-		}
+		/*
+		 * Given the core_clk (tclk_hz) and the target rate (speed) we
+		 * determine the best values for SPR (in [0 .. 15]) and SPPR (in
+		 * [0..7]) such that
+		 *
+		 * 	core_clk / (SPR * 2 ** SPPR)
+		 *
+		 * is as big as possible but not bigger than speed.
+		 */
 
-		if ((best_sppr == 0) && (best_spr == 0))
-			return -EINVAL;
+		/* best integer divider: */
+		unsigned divider = DIV_ROUND_UP(tclk_hz, speed);
+		unsigned spr, sppr;
+
+		if (divider < 16) {
+			/* This is the easy case, divider is less than 16 */
+			spr = divider;
+			sppr = 0;
+
+		} else {
+			unsigned two_pow_sppr;
+			/*
+			 * Find the highest bit set in divider. This and the
+			 * three next bits define SPR (apart from rounding).
+			 * SPPR is then the number of zero bits that must be
+			 * appended:
+			 */
+			sppr = fls(divider) - 4;
+
+			/*
+			 * As SPR only has 4 bits, we have to round divider up
+			 * to the next multiple of 2 ** sppr.
+			 */
+			two_pow_sppr = 1 << sppr;
+			divider = (divider + two_pow_sppr - 1) & -two_pow_sppr;
+
+			/*
+			 * recalculate sppr as rounding up divider might have
+			 * increased it enough to change the position of the
+			 * highest set bit. In this case the bit that now
+			 * doesn't make it into SPR is 0, so there is no need to
+			 * round again.
+			 */
+			sppr = fls(divider) - 4;
+			spr = divider >> sppr;
+
+			/*
+			 * Now do range checking. SPR is constructed to have a
+			 * width of 4 bits, so this is fine for sure. So we
+			 * still need to check for sppr to fit into 3 bits:
+			 */
+			if (sppr > 7)
+				return -EINVAL;
+		}
 
-		prescale = ((best_sppr & 0x6) << 5) |
-			((best_sppr & 0x1) << 4) | best_spr;
+		prescale = ((sppr & 0x6) << 5) | ((sppr & 0x1) << 4) | spr;
 	} else {
 		/*
 		 * the supported rates are: 4,6,8...30

tools/spi/spidev_test.c

@@ -315,7 +315,7 @@ static void transfer_file(int fd, char *filename)
 		pabort("can't stat input file");
 
 	tx_fd = open(filename, O_RDONLY);
-	if (fd < 0)
+	if (tx_fd < 0)
 		pabort("can't open input file");
 
 	tx = malloc(sb.st_size);