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path: root/drivers/spi/spidev.c
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Diffstat (limited to 'drivers/spi/spidev.c')
-rw-r--r--drivers/spi/spidev.c115
1 files changed, 76 insertions, 39 deletions
diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index e5e0cfed5e3..e3bc23bb588 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -1,5 +1,5 @@
/*
- * spidev.c -- simple synchronous userspace interface to SPI devices
+ * Simple synchronous userspace interface to SPI devices
*
* Copyright (C) 2006 SWAPP
* Andrea Paterniani <a.paterniani@swapp-eng.it>
@@ -30,19 +30,21 @@
#include <linux/errno.h>
#include <linux/mutex.h>
#include <linux/slab.h>
-#include <linux/smp_lock.h>
+#include <linux/compat.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/spi/spi.h>
#include <linux/spi/spidev.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
/*
- * This supports acccess to SPI devices using normal userspace I/O calls.
+ * This supports access to SPI devices using normal userspace I/O calls.
* Note that while traditional UNIX/POSIX I/O semantics are half duplex,
* and often mask message boundaries, full SPI support requires full duplex
- * transfers. There are several kinds of of internal message boundaries to
+ * transfers. There are several kinds of internal message boundaries to
* handle chipselect management and other protocol options.
*
* SPI has a character major number assigned. We allocate minor numbers
@@ -54,19 +56,25 @@
#define SPIDEV_MAJOR 153 /* assigned */
#define N_SPI_MINORS 32 /* ... up to 256 */
-static unsigned long minors[N_SPI_MINORS / BITS_PER_LONG];
+static DECLARE_BITMAP(minors, N_SPI_MINORS);
/* Bit masks for spi_device.mode management. Note that incorrect
- * settings for CS_HIGH and 3WIRE can cause *lots* of trouble for other
- * devices on a shared bus: CS_HIGH, because this device will be
- * active when it shouldn't be; 3WIRE, because when active it won't
- * behave as it should.
+ * settings for some settings can cause *lots* of trouble for other
+ * devices on a shared bus:
*
- * REVISIT should changing those two modes be privileged?
+ * - CS_HIGH ... this device will be active when it shouldn't be
+ * - 3WIRE ... when active, it won't behave as it should
+ * - NO_CS ... there will be no explicit message boundaries; this
+ * is completely incompatible with the shared bus model
+ * - READY ... transfers may proceed when they shouldn't.
+ *
+ * REVISIT should changing those flags be privileged?
*/
#define SPI_MODE_MASK (SPI_CPHA | SPI_CPOL | SPI_CS_HIGH \
- | SPI_LSB_FIRST | SPI_3WIRE | SPI_LOOP)
+ | SPI_LSB_FIRST | SPI_3WIRE | SPI_LOOP \
+ | SPI_NO_CS | SPI_READY | SPI_TX_DUAL \
+ | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)
struct spidev_data {
dev_t devt;
@@ -199,9 +207,9 @@ spidev_write(struct file *filp, const char __user *buf,
mutex_lock(&spidev->buf_lock);
missing = copy_from_user(spidev->buffer, buf, count);
- if (missing == 0) {
+ if (missing == 0)
status = spidev_sync_write(spidev, count);
- } else
+ else
status = -EFAULT;
mutex_unlock(&spidev->buf_lock);
@@ -258,19 +266,21 @@ static int spidev_message(struct spidev_data *spidev,
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;
#ifdef VERBOSE
- dev_dbg(&spi->dev,
+ dev_dbg(&spidev->spi->dev,
" xfer len %zd %s%s%s%dbits %u usec %uHz\n",
u_tmp->len,
u_tmp->rx_buf ? "rx " : "",
u_tmp->tx_buf ? "tx " : "",
u_tmp->cs_change ? "cs " : "",
- u_tmp->bits_per_word ? : spi->bits_per_word,
+ u_tmp->bits_per_word ? : spidev->spi->bits_per_word,
u_tmp->delay_usecs,
- u_tmp->speed_hz ? : spi->max_speed_hz);
+ u_tmp->speed_hz ? : spidev->spi->max_speed_hz);
#endif
spi_message_add_tail(k_tmp, &msg);
}
@@ -352,6 +362,10 @@ spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
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);
@@ -365,9 +379,13 @@ spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
/* 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;
@@ -375,18 +393,18 @@ spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
}
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;
@@ -467,12 +485,21 @@ spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return retval;
}
+#ifdef CONFIG_COMPAT
+static long
+spidev_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+ return spidev_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
+}
+#else
+#define spidev_compat_ioctl NULL
+#endif /* CONFIG_COMPAT */
+
static int spidev_open(struct inode *inode, struct file *filp)
{
struct spidev_data *spidev;
int status = -ENXIO;
- lock_kernel();
mutex_lock(&device_list_lock);
list_for_each_entry(spidev, &device_list, device_entry) {
@@ -498,7 +525,6 @@ static int spidev_open(struct inode *inode, struct file *filp)
pr_debug("spidev: nothing for minor %d\n", iminor(inode));
mutex_unlock(&device_list_lock);
- unlock_kernel();
return status;
}
@@ -532,7 +558,7 @@ static int spidev_release(struct inode *inode, struct file *filp)
return status;
}
-static struct file_operations spidev_fops = {
+static const struct file_operations spidev_fops = {
.owner = THIS_MODULE,
/* REVISIT switch to aio primitives, so that userspace
* gets more complete API coverage. It'll simplify things
@@ -541,8 +567,10 @@ static struct file_operations spidev_fops = {
.write = spidev_write,
.read = spidev_read,
.unlocked_ioctl = spidev_ioctl,
+ .compat_ioctl = spidev_compat_ioctl,
.open = spidev_open,
.release = spidev_release,
+ .llseek = no_llseek,
};
/*-------------------------------------------------------------------------*/
@@ -583,11 +611,10 @@ static int spidev_probe(struct spi_device *spi)
struct device *dev;
spidev->devt = MKDEV(SPIDEV_MAJOR, minor);
- dev = device_create_drvdata(spidev_class, &spi->dev,
- spidev->devt, spidev,
- "spidev%d.%d",
- spi->master->bus_num, spi->chip_select);
- status = IS_ERR(dev) ? PTR_ERR(dev) : 0;
+ dev = device_create(spidev_class, &spi->dev, spidev->devt,
+ spidev, "spidev%d.%d",
+ spi->master->bus_num, spi->chip_select);
+ status = PTR_ERR_OR_ZERO(dev);
} else {
dev_dbg(&spi->dev, "no minor number available!\n");
status = -ENODEV;
@@ -598,7 +625,9 @@ static int spidev_probe(struct spi_device *spi)
}
mutex_unlock(&device_list_lock);
- if (status != 0)
+ if (status == 0)
+ spi_set_drvdata(spi, spidev);
+ else
kfree(spidev);
return status;
@@ -611,7 +640,6 @@ static int spidev_remove(struct spi_device *spi)
/* 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 */
@@ -626,13 +654,21 @@ static int spidev_remove(struct spi_device *spi)
return 0;
}
-static struct spi_driver spidev_spi = {
+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,
- .remove = __devexit_p(spidev_remove),
+ .remove = spidev_remove,
/* NOTE: suspend/resume methods are not necessary here.
* We don't do anything except pass the requests to/from
@@ -658,14 +694,14 @@ static int __init spidev_init(void)
spidev_class = class_create(THIS_MODULE, "spidev");
if (IS_ERR(spidev_class)) {
- unregister_chrdev(SPIDEV_MAJOR, spidev_spi.driver.name);
+ unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name);
return PTR_ERR(spidev_class);
}
- status = spi_register_driver(&spidev_spi);
+ status = spi_register_driver(&spidev_spi_driver);
if (status < 0) {
class_destroy(spidev_class);
- unregister_chrdev(SPIDEV_MAJOR, spidev_spi.driver.name);
+ unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name);
}
return status;
}
@@ -673,12 +709,13 @@ module_init(spidev_init);
static void __exit spidev_exit(void)
{
- spi_unregister_driver(&spidev_spi);
+ spi_unregister_driver(&spidev_spi_driver);
class_destroy(spidev_class);
- unregister_chrdev(SPIDEV_MAJOR, spidev_spi.driver.name);
+ unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name);
}
module_exit(spidev_exit);
MODULE_AUTHOR("Andrea Paterniani, <a.paterniani@swapp-eng.it>");
MODULE_DESCRIPTION("User mode SPI device interface");
MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:spidev");
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-05 18:31:14 +0000