--- zzzz-none-000/linux-3.10.107/drivers/spi/spidev.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/spi/spidev.c	2021-02-04 17:41:59.000000000 +0000
@@ -14,10 +14,6 @@
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
 #include <linux/init.h>
@@ -37,7 +33,7 @@
 #include <linux/spi/spi.h>
 #include <linux/spi/spidev.h>
 
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
 
 
 /*
@@ -73,7 +69,8 @@
  */
 #define SPI_MODE_MASK		(SPI_CPHA | SPI_CPOL | SPI_CS_HIGH \
 				| SPI_LSB_FIRST | SPI_3WIRE | SPI_LOOP \
-				| SPI_NO_CS | SPI_READY)
+				| SPI_NO_CS | SPI_READY | SPI_TX_DUAL \
+				| SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)
 
 struct spidev_data {
 	dev_t			devt;
@@ -81,10 +78,12 @@
 	struct spi_device	*spi;
 	struct list_head	device_entry;
 
-	/* buffer is NULL unless this device is open (users > 0) */
+	/* TX/RX buffers are NULL unless this device is open (users > 0) */
 	struct mutex		buf_lock;
 	unsigned		users;
-	u8			*buffer;
+	u8			*tx_buffer;
+	u8			*rx_buffer;
+	u32			speed_hz;
 };
 
 static LIST_HEAD(device_list);
@@ -96,37 +95,25 @@
 
 /*-------------------------------------------------------------------------*/
 
-/*
- * We can't use the standard synchronous wrappers for file I/O; we
- * need to protect against async removal of the underlying spi_device.
- */
-static void spidev_complete(void *arg)
-{
-	complete(arg);
-}
-
 static ssize_t
 spidev_sync(struct spidev_data *spidev, struct spi_message *message)
 {
 	DECLARE_COMPLETION_ONSTACK(done);
 	int status;
-
-	message->complete = spidev_complete;
-	message->context = &done;
+	struct spi_device *spi;
 
 	spin_lock_irq(&spidev->spi_lock);
-	if (spidev->spi == NULL)
+	spi = spidev->spi;
+	spin_unlock_irq(&spidev->spi_lock);
+
+	if (spi == NULL)
 		status = -ESHUTDOWN;
 	else
-		status = spi_async(spidev->spi, message);
-	spin_unlock_irq(&spidev->spi_lock);
+		status = spi_sync(spi, message);
+
+	if (status == 0)
+		status = message->actual_length;
 
-	if (status == 0) {
-		wait_for_completion(&done);
-		status = message->status;
-		if (status == 0)
-			status = message->actual_length;
-	}
 	return status;
 }
 
@@ -134,8 +121,9 @@
 spidev_sync_write(struct spidev_data *spidev, size_t len)
 {
 	struct spi_transfer	t = {
-			.tx_buf		= spidev->buffer,
+			.tx_buf		= spidev->tx_buffer,
 			.len		= len,
+			.speed_hz	= spidev->speed_hz,
 		};
 	struct spi_message	m;
 
@@ -148,8 +136,9 @@
 spidev_sync_read(struct spidev_data *spidev, size_t len)
 {
 	struct spi_transfer	t = {
-			.rx_buf		= spidev->buffer,
+			.rx_buf		= spidev->rx_buffer,
 			.len		= len,
+			.speed_hz	= spidev->speed_hz,
 		};
 	struct spi_message	m;
 
@@ -178,7 +167,7 @@
 	if (status > 0) {
 		unsigned long	missing;
 
-		missing = copy_to_user(buf, spidev->buffer, status);
+		missing = copy_to_user(buf, spidev->rx_buffer, status);
 		if (missing == status)
 			status = -EFAULT;
 		else
@@ -205,10 +194,10 @@
 	spidev = filp->private_data;
 
 	mutex_lock(&spidev->buf_lock);
-	missing = copy_from_user(spidev->buffer, buf, count);
-	if (missing == 0) {
+	missing = copy_from_user(spidev->tx_buffer, buf, count);
+	if (missing == 0)
 		status = spidev_sync_write(spidev, count);
-	} else
+	else
 		status = -EFAULT;
 	mutex_unlock(&spidev->buf_lock);
 
@@ -222,8 +211,8 @@
 	struct spi_transfer	*k_xfers;
 	struct spi_transfer	*k_tmp;
 	struct spi_ioc_transfer *u_tmp;
-	unsigned		n, total;
-	u8			*buf;
+	unsigned		n, total, tx_total, rx_total;
+	u8			*tx_buf, *rx_buf;
 	int			status = -EFAULT;
 
 	spi_message_init(&msg);
@@ -235,42 +224,64 @@
 	 * We walk the array of user-provided transfers, using each one
 	 * to initialize a kernel version of the same transfer.
 	 */
-	buf = spidev->buffer;
+	tx_buf = spidev->tx_buffer;
+	rx_buf = spidev->rx_buffer;
 	total = 0;
+	tx_total = 0;
+	rx_total = 0;
 	for (n = n_xfers, k_tmp = k_xfers, u_tmp = u_xfers;
 			n;
 			n--, k_tmp++, u_tmp++) {
 		k_tmp->len = u_tmp->len;
 
 		total += k_tmp->len;
-		/* Check total length of transfers.  Also check each
-		 * transfer length to avoid arithmetic overflow.
+		/* Since the function returns the total length of transfers
+		 * on success, restrict the total to positive int values to
+		 * avoid the return value looking like an error.  Also check
+		 * each transfer length to avoid arithmetic overflow.
 		 */
-		if (total > bufsiz || k_tmp->len > bufsiz) {
+		if (total > INT_MAX || k_tmp->len > INT_MAX) {
 			status = -EMSGSIZE;
 			goto done;
 		}
 
 		if (u_tmp->rx_buf) {
-			k_tmp->rx_buf = buf;
+			/* this transfer needs space in RX bounce buffer */
+			rx_total += k_tmp->len;
+			if (rx_total > bufsiz) {
+				status = -EMSGSIZE;
+				goto done;
+			}
+			k_tmp->rx_buf = rx_buf;
 			if (!access_ok(VERIFY_WRITE, (u8 __user *)
 						(uintptr_t) u_tmp->rx_buf,
 						u_tmp->len))
 				goto done;
+			rx_buf += k_tmp->len;
 		}
 		if (u_tmp->tx_buf) {
-			k_tmp->tx_buf = buf;
-			if (copy_from_user(buf, (const u8 __user *)
+			/* this transfer needs space in TX bounce buffer */
+			tx_total += k_tmp->len;
+			if (tx_total > bufsiz) {
+				status = -EMSGSIZE;
+				goto done;
+			}
+			k_tmp->tx_buf = tx_buf;
+			if (copy_from_user(tx_buf, (const u8 __user *)
 						(uintptr_t) u_tmp->tx_buf,
 					u_tmp->len))
 				goto done;
+			tx_buf += k_tmp->len;
 		}
-		buf += k_tmp->len;
 
 		k_tmp->cs_change = !!u_tmp->cs_change;
+		k_tmp->tx_nbits = u_tmp->tx_nbits;
+		k_tmp->rx_nbits = u_tmp->rx_nbits;
 		k_tmp->bits_per_word = u_tmp->bits_per_word;
 		k_tmp->delay_usecs = u_tmp->delay_usecs;
 		k_tmp->speed_hz = u_tmp->speed_hz;
+		if (!k_tmp->speed_hz)
+			k_tmp->speed_hz = spidev->speed_hz;
 #ifdef VERBOSE
 		dev_dbg(&spidev->spi->dev,
 			"  xfer len %zd %s%s%s%dbits %u usec %uHz\n",
@@ -290,17 +301,17 @@
 		goto done;
 
 	/* copy any rx data out of bounce buffer */
-	buf = spidev->buffer;
+	rx_buf = spidev->rx_buffer;
 	for (n = n_xfers, u_tmp = u_xfers; n; n--, u_tmp++) {
 		if (u_tmp->rx_buf) {
 			if (__copy_to_user((u8 __user *)
-					(uintptr_t) u_tmp->rx_buf, buf,
+					(uintptr_t) u_tmp->rx_buf, rx_buf,
 					u_tmp->len)) {
 				status = -EFAULT;
 				goto done;
 			}
+			rx_buf += u_tmp->len;
 		}
-		buf += u_tmp->len;
 	}
 	status = total;
 
@@ -309,6 +320,37 @@
 	return status;
 }
 
+static struct spi_ioc_transfer *
+spidev_get_ioc_message(unsigned int cmd, struct spi_ioc_transfer __user *u_ioc,
+		unsigned *n_ioc)
+{
+	struct spi_ioc_transfer	*ioc;
+	u32	tmp;
+
+	/* Check type, command number and direction */
+	if (_IOC_TYPE(cmd) != SPI_IOC_MAGIC
+			|| _IOC_NR(cmd) != _IOC_NR(SPI_IOC_MESSAGE(0))
+			|| _IOC_DIR(cmd) != _IOC_WRITE)
+		return ERR_PTR(-ENOTTY);
+
+	tmp = _IOC_SIZE(cmd);
+	if ((tmp % sizeof(struct spi_ioc_transfer)) != 0)
+		return ERR_PTR(-EINVAL);
+	*n_ioc = tmp / sizeof(struct spi_ioc_transfer);
+	if (*n_ioc == 0)
+		return NULL;
+
+	/* copy into scratch area */
+	ioc = kmalloc(tmp, GFP_KERNEL);
+	if (!ioc)
+		return ERR_PTR(-ENOMEM);
+	if (__copy_from_user(ioc, u_ioc, tmp)) {
+		kfree(ioc);
+		return ERR_PTR(-EFAULT);
+	}
+	return ioc;
+}
+
 static long
 spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
@@ -362,6 +404,10 @@
 		retval = __put_user(spi->mode & SPI_MODE_MASK,
 					(__u8 __user *)arg);
 		break;
+	case SPI_IOC_RD_MODE32:
+		retval = __put_user(spi->mode & SPI_MODE_MASK,
+					(__u32 __user *)arg);
+		break;
 	case SPI_IOC_RD_LSB_FIRST:
 		retval = __put_user((spi->mode & SPI_LSB_FIRST) ?  1 : 0,
 					(__u8 __user *)arg);
@@ -370,14 +416,18 @@
 		retval = __put_user(spi->bits_per_word, (__u8 __user *)arg);
 		break;
 	case SPI_IOC_RD_MAX_SPEED_HZ:
-		retval = __put_user(spi->max_speed_hz, (__u32 __user *)arg);
+		retval = __put_user(spidev->speed_hz, (__u32 __user *)arg);
 		break;
 
 	/* write requests */
 	case SPI_IOC_WR_MODE:
-		retval = __get_user(tmp, (u8 __user *)arg);
+	case SPI_IOC_WR_MODE32:
+		if (cmd == SPI_IOC_WR_MODE)
+			retval = __get_user(tmp, (u8 __user *)arg);
+		else
+			retval = __get_user(tmp, (u32 __user *)arg);
 		if (retval == 0) {
-			u8	save = spi->mode;
+			u32	save = spi->mode;
 
 			if (tmp & ~SPI_MODE_MASK) {
 				retval = -EINVAL;
@@ -385,18 +435,18 @@
 			}
 
 			tmp |= spi->mode & ~SPI_MODE_MASK;
-			spi->mode = (u8)tmp;
+			spi->mode = (u16)tmp;
 			retval = spi_setup(spi);
 			if (retval < 0)
 				spi->mode = save;
 			else
-				dev_dbg(&spi->dev, "spi mode %02x\n", tmp);
+				dev_dbg(&spi->dev, "spi mode %x\n", tmp);
 		}
 		break;
 	case SPI_IOC_WR_LSB_FIRST:
 		retval = __get_user(tmp, (__u8 __user *)arg);
 		if (retval == 0) {
-			u8	save = spi->mode;
+			u32	save = spi->mode;
 
 			if (tmp)
 				spi->mode |= SPI_LSB_FIRST;
@@ -430,41 +480,25 @@
 
 			spi->max_speed_hz = tmp;
 			retval = spi_setup(spi);
-			if (retval < 0)
-				spi->max_speed_hz = save;
+			if (retval >= 0)
+				spidev->speed_hz = tmp;
 			else
 				dev_dbg(&spi->dev, "%d Hz (max)\n", tmp);
+			spi->max_speed_hz = save;
 		}
 		break;
 
 	default:
 		/* segmented and/or full-duplex I/O request */
-		if (_IOC_NR(cmd) != _IOC_NR(SPI_IOC_MESSAGE(0))
-				|| _IOC_DIR(cmd) != _IOC_WRITE) {
-			retval = -ENOTTY;
-			break;
-		}
-
-		tmp = _IOC_SIZE(cmd);
-		if ((tmp % sizeof(struct spi_ioc_transfer)) != 0) {
-			retval = -EINVAL;
-			break;
-		}
-		n_ioc = tmp / sizeof(struct spi_ioc_transfer);
-		if (n_ioc == 0)
-			break;
-
-		/* copy into scratch area */
-		ioc = kmalloc(tmp, GFP_KERNEL);
-		if (!ioc) {
-			retval = -ENOMEM;
-			break;
-		}
-		if (__copy_from_user(ioc, (void __user *)arg, tmp)) {
-			kfree(ioc);
-			retval = -EFAULT;
+		/* Check message and copy into scratch area */
+		ioc = spidev_get_ioc_message(cmd,
+				(struct spi_ioc_transfer __user *)arg, &n_ioc);
+		if (IS_ERR(ioc)) {
+			retval = PTR_ERR(ioc);
 			break;
 		}
+		if (!ioc)
+			break;	/* n_ioc is also 0 */
 
 		/* translate to spi_message, execute */
 		retval = spidev_message(spidev, ioc, n_ioc);
@@ -479,8 +513,67 @@
 
 #ifdef CONFIG_COMPAT
 static long
+spidev_compat_ioc_message(struct file *filp, unsigned int cmd,
+		unsigned long arg)
+{
+	struct spi_ioc_transfer __user	*u_ioc;
+	int				retval = 0;
+	struct spidev_data		*spidev;
+	struct spi_device		*spi;
+	unsigned			n_ioc, n;
+	struct spi_ioc_transfer		*ioc;
+
+	u_ioc = (struct spi_ioc_transfer __user *) compat_ptr(arg);
+	if (!access_ok(VERIFY_READ, u_ioc, _IOC_SIZE(cmd)))
+		return -EFAULT;
+
+	/* guard against device removal before, or while,
+	 * we issue this ioctl.
+	 */
+	spidev = filp->private_data;
+	spin_lock_irq(&spidev->spi_lock);
+	spi = spi_dev_get(spidev->spi);
+	spin_unlock_irq(&spidev->spi_lock);
+
+	if (spi == NULL)
+		return -ESHUTDOWN;
+
+	/* SPI_IOC_MESSAGE needs the buffer locked "normally" */
+	mutex_lock(&spidev->buf_lock);
+
+	/* Check message and copy into scratch area */
+	ioc = spidev_get_ioc_message(cmd, u_ioc, &n_ioc);
+	if (IS_ERR(ioc)) {
+		retval = PTR_ERR(ioc);
+		goto done;
+	}
+	if (!ioc)
+		goto done;	/* n_ioc is also 0 */
+
+	/* Convert buffer pointers */
+	for (n = 0; n < n_ioc; n++) {
+		ioc[n].rx_buf = (uintptr_t) compat_ptr(ioc[n].rx_buf);
+		ioc[n].tx_buf = (uintptr_t) compat_ptr(ioc[n].tx_buf);
+	}
+
+	/* translate to spi_message, execute */
+	retval = spidev_message(spidev, ioc, n_ioc);
+	kfree(ioc);
+
+done:
+	mutex_unlock(&spidev->buf_lock);
+	spi_dev_put(spi);
+	return retval;
+}
+
+static long
 spidev_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
+	if (_IOC_TYPE(cmd) == SPI_IOC_MAGIC
+			&& _IOC_NR(cmd) == _IOC_NR(SPI_IOC_MESSAGE(0))
+			&& _IOC_DIR(cmd) == _IOC_WRITE)
+		return spidev_compat_ioc_message(filp, cmd, arg);
+
 	return spidev_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
 }
 #else
@@ -500,30 +593,48 @@
 			break;
 		}
 	}
-	if (status == 0) {
-		if (!spidev->buffer) {
-			spidev->buffer = kmalloc(bufsiz, GFP_KERNEL);
-			if (!spidev->buffer) {
-				dev_dbg(&spidev->spi->dev, "open/ENOMEM\n");
-				status = -ENOMEM;
-			}
+
+	if (status) {
+		pr_debug("spidev: nothing for minor %d\n", iminor(inode));
+		goto err_find_dev;
+	}
+
+	if (!spidev->tx_buffer) {
+		spidev->tx_buffer = kmalloc(bufsiz, GFP_KERNEL);
+		if (!spidev->tx_buffer) {
+			dev_dbg(&spidev->spi->dev, "open/ENOMEM\n");
+			status = -ENOMEM;
+			goto err_find_dev;
 		}
-		if (status == 0) {
-			spidev->users++;
-			filp->private_data = spidev;
-			nonseekable_open(inode, filp);
+	}
+
+	if (!spidev->rx_buffer) {
+		spidev->rx_buffer = kmalloc(bufsiz, GFP_KERNEL);
+		if (!spidev->rx_buffer) {
+			dev_dbg(&spidev->spi->dev, "open/ENOMEM\n");
+			status = -ENOMEM;
+			goto err_alloc_rx_buf;
 		}
-	} else
-		pr_debug("spidev: nothing for minor %d\n", iminor(inode));
+	}
+
+	spidev->users++;
+	filp->private_data = spidev;
+	nonseekable_open(inode, filp);
 
 	mutex_unlock(&device_list_lock);
+	return 0;
+
+err_alloc_rx_buf:
+	kfree(spidev->tx_buffer);
+	spidev->tx_buffer = NULL;
+err_find_dev:
+	mutex_unlock(&device_list_lock);
 	return status;
 }
 
 static int spidev_release(struct inode *inode, struct file *filp)
 {
 	struct spidev_data	*spidev;
-	int			status = 0;
 
 	mutex_lock(&device_list_lock);
 	spidev = filp->private_data;
@@ -534,11 +645,17 @@
 	if (!spidev->users) {
 		int		dofree;
 
-		kfree(spidev->buffer);
-		spidev->buffer = NULL;
+		kfree(spidev->tx_buffer);
+		spidev->tx_buffer = NULL;
+
+		kfree(spidev->rx_buffer);
+		spidev->rx_buffer = NULL;
 
-		/* ... after we unbound from the underlying device? */
 		spin_lock_irq(&spidev->spi_lock);
+		if (spidev->spi)
+			spidev->speed_hz = spidev->spi->max_speed_hz;
+
+		/* ... after we unbound from the underlying device? */
 		dofree = (spidev->spi == NULL);
 		spin_unlock_irq(&spidev->spi_lock);
 
@@ -547,7 +664,7 @@
 	}
 	mutex_unlock(&device_list_lock);
 
-	return status;
+	return 0;
 }
 
 static const struct file_operations spidev_fops = {
@@ -574,6 +691,16 @@
 
 static struct class *spidev_class;
 
+#ifdef CONFIG_OF
+static const struct of_device_id spidev_dt_ids[] = {
+	{ .compatible = "rohm,dh2228fv" },
+	{ .compatible = "lineartechnology,ltc2488" },
+	{ .compatible = "qca,spidev" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, spidev_dt_ids);
+#endif
+
 /*-------------------------------------------------------------------------*/
 
 static int spidev_probe(struct spi_device *spi)
@@ -582,6 +709,17 @@
 	int			status;
 	unsigned long		minor;
 
+	/*
+	 * spidev should never be referenced in DT without a specific
+	 * compatible string, it is a Linux implementation thing
+	 * rather than a description of the hardware.
+	 */
+	if (spi->dev.of_node && !of_match_device(spidev_dt_ids, &spi->dev)) {
+		dev_err(&spi->dev, "buggy DT: spidev listed directly in DT\n");
+		WARN_ON(spi->dev.of_node &&
+			!of_match_device(spidev_dt_ids, &spi->dev));
+	}
+
 	/* Allocate driver data */
 	spidev = kzalloc(sizeof(*spidev), GFP_KERNEL);
 	if (!spidev)
@@ -606,7 +744,7 @@
 		dev = device_create(spidev_class, &spi->dev, spidev->devt,
 				    spidev, "spidev%d.%d",
 				    spi->master->bus_num, spi->chip_select);
-		status = PTR_RET(dev);
+		status = PTR_ERR_OR_ZERO(dev);
 	} else {
 		dev_dbg(&spi->dev, "no minor number available!\n");
 		status = -ENODEV;
@@ -617,6 +755,8 @@
 	}
 	mutex_unlock(&device_list_lock);
 
+	spidev->speed_hz = spi->max_speed_hz;
+
 	if (status == 0)
 		spi_set_drvdata(spi, spidev);
 	else
@@ -632,7 +772,6 @@
 	/* make sure ops on existing fds can abort cleanly */
 	spin_lock_irq(&spidev->spi_lock);
 	spidev->spi = NULL;
-	spi_set_drvdata(spi, NULL);
 	spin_unlock_irq(&spidev->spi_lock);
 
 	/* prevent new opens */
@@ -647,17 +786,9 @@
 	return 0;
 }
 
-static const struct of_device_id spidev_dt_ids[] = {
-	{ .compatible = "rohm,dh2228fv" },
-	{},
-};
-
-MODULE_DEVICE_TABLE(of, spidev_dt_ids);
-
 static struct spi_driver spidev_spi_driver = {
 	.driver = {
 		.name =		"spidev",
-		.owner =	THIS_MODULE,
 		.of_match_table = of_match_ptr(spidev_dt_ids),
 	},
 	.probe =	spidev_probe,