spi: Updates for v3.10

A few driver specific fixes plus improved error handling in the generic
 DT GPIO chipselect handling - not exciting but useful.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQIcBAABAgAGBQJRkPjpAAoJELSic+t+oim955wP/RD+X7Y7VtDZ2NGwuMndRM0j
 F63XfXcqSTeQCq5KvOkOW0FUO8lY7MkPIMUE95PZ2jcQW4lXYo5vrhiW8vpn6+fk
 ALOqqx9fZfcf/zmi6FRDMqyqor8GSnHEXsif+4ZoP6dwyaKiqICk51Fk5ZEF4+ZQ
 98I6aEhxqz3I4J4KfBq5YVpdqpxaAG/USQE8IvLyAjKzJ8rLnfS4J7Uy9vfcSDW3
 /7KZoDqMysOXRBN5sNSiOjBg0xD3hnKlnCsQtlktK+zE2b4vJQZBLRv2gyjSrfV0
 GIcwlAandP9SD+rjKY1a8oLCj4P4h+u7TdVhKf3zdTOG5/IguvmiSMfgwoHFkhxn
 GmFD3yXNXp+pFtJHYGznQh3/+36uSKZmWLrYZtxS5X/AEYSl4wqczHoMgF9JvYiQ
 I+H59+lG3J4TfjSZ6sREcDPu231Sy2PMfyRgC+EFgi/W3F1IYC/apgGqA39MCo9H
 hP9oAxCNqcrzmdLsJ+Y3rM47wMGdTzYxcpkkEKZAAE04K5yU3+t/GZnqSXZv9bQO
 gxJHX9nPRgghWsMbg83RdrUuWARrV2i+Sd4sojFEztzC5nV1oDMOBotkqSAdwQ71
 h69lWxsOqDQwJhwvFc43TbWmMVWV8BjNthGbcjEM5+n0oaCPjJ4WfKITJvZol1xv
 kSmwaZ7514E7Le+otttD
 =FUCL
 -----END PGP SIGNATURE-----

Merge tag 'spi-v3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi updates from Mark Brown:
 "A few driver specific fixes plus improved error handling in the
  generic DT GPIO chipselect handling - not exciting but useful."

* tag 'spi-v3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi/spi-atmel: BUG: fix doesn' support 16 bits transfers using PIO
  spi/davinci: fix module build error
  spi: Return error from of_spi_register_master on bad "cs-gpios" property
  spi: Initialize cs_gpio and cs_gpios with -ENOENT
  spi/atmel: fix speed_hz check in atmel_spi_transfer()

drivers/spi/spi-atmel.c

@@ -526,13 +526,17 @@ static void atmel_spi_next_xfer_pio(struct spi_master *master,
 	}
 
 	if (xfer->tx_buf)
+		if (xfer->bits_per_word > 8)
+			spi_writel(as, TDR, *(u16 *)(xfer->tx_buf));
+		else
 			spi_writel(as, TDR, *(u8 *)(xfer->tx_buf));
 	else
 		spi_writel(as, TDR, 0);
 
 	dev_dbg(master->dev.parent,
-		"  start pio xfer %p: len %u tx %p rx %p\n",
+		"  start pio xfer %p: len %u tx %p rx %p bitpw %d\n",
-		xfer, xfer->len, xfer->tx_buf, xfer->rx_buf);
+		xfer, xfer->len, xfer->tx_buf, xfer->rx_buf,
+		xfer->bits_per_word);
 
 	/* Enable relevant interrupts */
 	spi_writel(as, IER, SPI_BIT(RDRF) | SPI_BIT(OVRES));
@@ -950,21 +954,39 @@ atmel_spi_pump_pio_data(struct atmel_spi *as, struct spi_transfer *xfer)
 {
 	u8		*txp;
 	u8		*rxp;
+	u16		*txp16;
+	u16		*rxp16;
 	unsigned long	xfer_pos = xfer->len - as->current_remaining_bytes;
 
 	if (xfer->rx_buf) {
+		if (xfer->bits_per_word > 8) {
+			rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos);
+			*rxp16 = spi_readl(as, RDR);
+		} else {
 			rxp = ((u8 *)xfer->rx_buf) + xfer_pos;
 			*rxp = spi_readl(as, RDR);
+		}
 	} else {
 		spi_readl(as, RDR);
 	}
-
+	if (xfer->bits_per_word > 8) {
+		as->current_remaining_bytes -= 2;
+		if (as->current_remaining_bytes < 0)
+			as->current_remaining_bytes = 0;
+	} else {
 		as->current_remaining_bytes--;
+	}
 
 	if (as->current_remaining_bytes) {
 		if (xfer->tx_buf) {
+			if (xfer->bits_per_word > 8) {
+				txp16 = (u16 *)(((u8 *)xfer->tx_buf)
+							+ xfer_pos + 2);
+				spi_writel(as, TDR, *txp16);
+			} else {
 				txp = ((u8 *)xfer->tx_buf) + xfer_pos + 1;
 				spi_writel(as, TDR, *txp);
+			}
 		} else {
 			spi_writel(as, TDR, 0);
 		}
@@ -1378,9 +1400,16 @@ static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg)
 			}
 		}
 
+		if (xfer->bits_per_word > 8) {
+			if (xfer->len % 2) {
+				dev_dbg(&spi->dev, "buffer len should be 16 bits aligned\n");
+				return -EINVAL;
+			}
+		}
+
 		/* FIXME implement these protocol options!! */
-		if (xfer->speed_hz) {
+		if (xfer->speed_hz < spi->max_speed_hz) {
-			dev_dbg(&spi->dev, "no protocol options yet\n");
+			dev_dbg(&spi->dev, "can't change speed in transfer\n");
 			return -ENOPROTOOPT;
 		}
 

drivers/spi/spi-davinci.c

@@ -784,7 +784,7 @@ static const struct of_device_id davinci_spi_of_match[] = {
 	},
 	{ },
 };
-MODULE_DEVICE_TABLE(of, davini_spi_of_match);
+MODULE_DEVICE_TABLE(of, davinci_spi_of_match);
 
 /**
  * spi_davinci_get_pdata - Get platform data from DTS binding

drivers/spi/spi.c

@@ -334,7 +334,7 @@ struct spi_device *spi_alloc_device(struct spi_master *master)
 	spi->dev.parent = &master->dev;
 	spi->dev.bus = &spi_bus_type;
 	spi->dev.release = spidev_release;
-	spi->cs_gpio = -EINVAL;
+	spi->cs_gpio = -ENOENT;
 	device_initialize(&spi->dev);
 	return spi;
 }
@@ -1067,8 +1067,11 @@ static int of_spi_register_master(struct spi_master *master)
 	nb = of_gpio_named_count(np, "cs-gpios");
 	master->num_chipselect = max(nb, (int)master->num_chipselect);
 
-	if (nb < 1)
+	/* Return error only for an incorrectly formed cs-gpios property */
+	if (nb == 0 || nb == -ENOENT)
 		return 0;
+	else if (nb < 0)
+		return nb;
 
 	cs = devm_kzalloc(&master->dev,
 			  sizeof(int) * master->num_chipselect,
@@ -1079,7 +1082,7 @@ static int of_spi_register_master(struct spi_master *master)
 		return -ENOMEM;
 
 	for (i = 0; i < master->num_chipselect; i++)
-		cs[i] = -EINVAL;
+		cs[i] = -ENOENT;
 
 	for (i = 0; i < nb; i++)
 		cs[i] = of_get_named_gpio(np, "cs-gpios", i);

include/linux/spi/spi.h

@@ -57,7 +57,7 @@ extern struct bus_type spi_bus_type;
  * @modalias: Name of the driver to use with this device, or an alias
  *	for that name.  This appears in the sysfs "modalias" attribute
  *	for driver coldplugging, and in uevents used for hotplugging
- * @cs_gpio: gpio number of the chipselect line (optional, -EINVAL when
+ * @cs_gpio: gpio number of the chipselect line (optional, -ENOENT when
  *	when not using a GPIO line)
  *
  * A @spi_device is used to interchange data between an SPI slave
@@ -266,7 +266,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
  *	queue so the subsystem notifies the driver that it may relax the
  *	hardware by issuing this call
  * @cs_gpios: Array of GPIOs to use as chip select lines; one per CS
- *	number. Any individual value may be -EINVAL for CS lines that
+ *	number. Any individual value may be -ENOENT for CS lines that
  *	are not GPIOs (driven by the SPI controller itself).
  *
  * Each SPI master controller can communicate with one or more @spi_device