PL2303 USB Serial devices always has GPIOs, this patch add
generic gpio support interfaces for pl2303 USB Serial devices
in pl2303_type_data and pl2303_serial_private, then use them
to add GPIOs support for one type of them, PL2303HXA.
Known issue:
If gpios are in use(export to userspace through sysfs interface, etc),
then call pl2303_release(unplug usb-serial convertor, modprobe -r, etc),
will cause trouble, so we need to make sure there is no gpio user before
call pl2303_release.
Signed-off-by: Wang YanQing <udknight@xxxxxxxxx>
---
Changes
v6-v7:
1: add generic gpio support interfaces for pl2303 USB Serial devices
in pl2303_type_data and pl2303_serial_private suggested by Andreas Mohr.
2: drop different label names for different pl2303 instance suggested by Johan Hovold.
3: fix missing lock corrected by Johan Hovold.
4: use prefix pl2303hx_gpio instead pl2303_gpio, pl2303_gpio is over generic for current code,
and now we move gpio_startup|gpio_release into type-specified data structure, so pl2303hx_gpio
is a better prefix.
5: make words in Kconfig a little more useful and clarified.
6: many misc code quality enhancement suggested by Johan Hovold.
v5-v6:
1: fix typo error in Kconfig reported by Andreas Mohr
2: add const qulification to gpio_dir_mask and gpio_value_mask suggested by Andreas Mohr
v4-v5:
1: fix gpio_chip.lable been overwrited by template_chip.
2: use idr to manage minor instead of crude monotonous atomic increment.
v3-v4:
1: fix missing static for gpio_dir_mask and gpio_value_mask
2: reduce unneeded compile macro defined suggested by gnomes@xxxxxxxxxxxxxxxxxxx
3: use true instead of 1 corrected by Linus Walleij
4: ignore return value of gpiochip_remove suggested by Linus Walleij
5: fix multi gpio_chips registered by pl2303 can't be distinguished in kernel space.
v2-v3:
1: fix errors and warnings reported by Daniele Forsi checked with checkpatch.pl
2: fix missing GPIOLIB dependence in Kconfig
3: fix pl2303_gpio_get can't work
v1-v2:
1:drop gpio-pl2303.c and relation stuff
2:hang gpio stuff off of pl2303.c
drivers/usb/serial/Kconfig | 10 +++
drivers/usb/serial/pl2303.c | 202 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 212 insertions(+)
diff --git a/drivers/usb/serial/Kconfig b/drivers/usb/serial/Kconfig
index 3ce5c74..008ec57 100644
--- a/drivers/usb/serial/Kconfig
+++ b/drivers/usb/serial/Kconfig
@@ -516,6 +516,16 @@ config USB_SERIAL_PL2303
To compile this driver as a module, choose M here: the
module will be called pl2303.
+config USB_SERIAL_PL2303_GPIO
+ bool "USB Prolific 2303 Single Port GPIOs support"
+ depends on USB_SERIAL_PL2303 && GPIOLIB
+ ---help---
+ Say Y here if you want to use GPIOs on PL2303 USB Serial single port
+ adapter from Prolific.
+
+ It supports 2 dedicated GPIOs on PL2303HXA only currently.
+ If unsure, say N.
+
config USB_SERIAL_OTI6858
tristate "USB Ours Technology Inc. OTi-6858 USB To RS232 Bridge Controller"
help
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index b3d5a35..edbe634 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -28,6 +28,8 @@
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <asm/unaligned.h>
+#include <linux/gpio.h>
+#include <linux/mutex.h>
#include "pl2303.h"
@@ -131,6 +133,8 @@ MODULE_DEVICE_TABLE(usb, id_table);
#define UART_OVERRUN_ERROR 0x40
#define UART_CTS 0x80
+#define PL2303HX_REG_GPIO_CONTROL 0x01
+#define PL2303HX_REG_GPIO_STATE 0x81
enum pl2303_type {
TYPE_01, /* Type 0 and 1 (difference unknown) */
@@ -141,11 +145,15 @@ enum pl2303_type {
struct pl2303_type_data {
speed_t max_baud_rate;
unsigned long quirks;
+ u16 ngpio;
+ int (*gpio_startup)(struct usb_serial *serial);
+ void (*gpio_release)(struct usb_serial *serial);
};
struct pl2303_serial_private {
const struct pl2303_type_data *type;
unsigned long quirks;
+ void *gpio;
};
struct pl2303_private {
@@ -156,11 +164,24 @@ struct pl2303_private {
u8 line_settings[7];
};
+#ifdef CONFIG_USB_SERIAL_PL2303_GPIO
+static int pl2303hx_gpio_startup(struct usb_serial *serial);
+static void pl2303hx_gpio_release(struct usb_serial *serial);
+#else
+static inline int pl2303hx_gpio_startup(struct usb_serial *serial) { return 0; }
+static inline void pl2303hx_gpio_release(struct usb_serial *serial) {}
+#endif
+
static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
[TYPE_01] = {
.max_baud_rate = 1228800,
.quirks = PL2303_QUIRK_LEGACY,
},
+ [TYPE_HX] = {
+ .ngpio = 2,
+ .gpio_startup = pl2303hx_gpio_startup,
+ .gpio_release = pl2303hx_gpio_release,
+ }
};
static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
@@ -213,6 +234,176 @@ static int pl2303_probe(struct usb_serial *serial,
return 0;
}
+#ifdef CONFIG_USB_SERIAL_PL2303_GPIO
+struct pl2303hx_gpio_data {
+ /*
+ * 0..3: unknown (zero)
+ * 4: gp0 output enable (1: gp0 pin is output, 0: gp0 pin is input)
+ * 5: gp1 output enable (1: gp1 pin is output, 0: gp1 pin is input)
+ * 6: gp0 pin value
+ * 7: gp1 pin value
+ */
+ u8 index;
+ struct mutex lock;
+ struct usb_serial *serial;
+ struct gpio_chip gpio_chip;
+};
+
+static inline struct pl2303hx_gpio_data *to_pl2303hx_gpio_data(struct gpio_chip *chip)
+{
+ return container_of(chip, struct pl2303hx_gpio_data, gpio_chip);
+}
+
+static u8 pl2303hx_gpio_dir_mask(unsigned offset)
+{
+ switch(offset)
+ {
+ case 0:
+ return 0x10;
+ case 1:
+ return 0x20;
+ default:
+ break;
+ };
+ return 0;
+}
+
+static u8 pl2303hx_gpio_value_mask(unsigned offset)
+{
+ switch(offset)
+ {
+ case 0:
+ return 0x40;
+ case 1:
+ return 0x80;
+ default:
+ break;
+ };
+ return 0;
+}
+
+static int pl2303hx_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
+{
+ struct pl2303hx_gpio_data *gpio = to_pl2303hx_gpio_data(chip);
+ int ret;
+
+ mutex_lock(&gpio->lock);
+ gpio->index &= ~pl2303hx_gpio_dir_mask(offset);
+ ret = pl2303_vendor_write(gpio->serial, PL2303HX_REG_GPIO_CONTROL, gpio->index);
+ mutex_unlock(&gpio->lock);
+
+ return ret;
+}
+
+static int pl2303hx_gpio_direction_out(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ struct pl2303hx_gpio_data *gpio = to_pl2303hx_gpio_data(chip);
+ int ret;
+
+ mutex_lock(&gpio->lock);
+ gpio->index |= pl2303hx_gpio_dir_mask(offset);
+ if (value)
+ gpio->index |= pl2303hx_gpio_value_mask(offset);
+ else
+ gpio->index &= ~pl2303hx_gpio_value_mask(offset);
+
+ ret = pl2303_vendor_write(gpio->serial, PL2303HX_REG_GPIO_CONTROL, gpio->index);
+ mutex_unlock(&gpio->lock);
+
+ return ret;
+}
+
+static void pl2303hx_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct pl2303hx_gpio_data *gpio = to_pl2303hx_gpio_data(chip);
+
+ mutex_lock(&gpio->lock);
+ if (value)
+ gpio->index |= pl2303hx_gpio_value_mask(offset);
+ else
+ gpio->index &= ~pl2303hx_gpio_value_mask(offset);
+
+ pl2303_vendor_write(gpio->serial, PL2303HX_REG_GPIO_CONTROL, gpio->index);
+ mutex_unlock(&gpio->lock);
+}
+
+static int pl2303hx_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct pl2303hx_gpio_data *gpio = to_pl2303hx_gpio_data(chip);
+ unsigned char *buf;
+ int value = 0;
+
+ buf = kmalloc(1, GFP_KERNEL);
+ if (!buf) {
+ return -ENOMEM;
+ }
+
+ mutex_lock(&gpio->lock);
+ if (pl2303_vendor_read(gpio->serial, PL2303HX_REG_GPIO_STATE, buf)) {
+ mutex_unlock(&gpio->lock);
+ return -EIO;
+ }
+
+ value = buf[0] & pl2303hx_gpio_value_mask(offset);
+ mutex_unlock(&gpio->lock);
+ kfree(buf);
+
+ return value;
+}
+
+static int pl2303hx_gpio_startup(struct usb_serial *serial)
+{
+ struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
+ struct pl2303hx_gpio_data *gpio;
+ int ret;
+
+ gpio = kzalloc(sizeof(struct pl2303hx_gpio_data), GFP_KERNEL);
+ if (!gpio) {
+ dev_err(&serial->interface->dev,
+ "Failed to allocate pl2303_gpio_data\n");
+ return -ENOMEM;
+ }
+
+ gpio->index = 0x00;
+ gpio->serial = serial;
+ mutex_init(&gpio->lock);
+
+ gpio->gpio_chip.label = "pl2303";
+ gpio->gpio_chip.owner = THIS_MODULE;
+ gpio->gpio_chip.direction_input = pl2303hx_gpio_direction_in;
+ gpio->gpio_chip.get = pl2303hx_gpio_get;
+ gpio->gpio_chip.direction_output = pl2303hx_gpio_direction_out;
+ gpio->gpio_chip.set = pl2303hx_gpio_set;
+ gpio->gpio_chip.can_sleep = true;
+ gpio->gpio_chip.ngpio = spriv->type->ngpio;
+ gpio->gpio_chip.base = -1;
+ gpio->gpio_chip.dev = &serial->interface->dev;
+
+ /* initialize GPIOs, input mode as default */
+ pl2303_vendor_write(gpio->serial, PL2303HX_REG_GPIO_CONTROL, gpio->index);
+
+ ret = gpiochip_add(&gpio->gpio_chip);
+ if (ret < 0) {
+ dev_err(&serial->interface->dev,
+ "Could not register gpiochip, %d\n", ret);
+ kfree(gpio);
+ return ret;
+ }
+ spriv->gpio = gpio;
+ return 0;
+}
+
+static void pl2303hx_gpio_release(struct usb_serial *serial)
+{
+ struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
+ struct pl2303hx_gpio_data *gpio = (struct pl2303hx_gpio_data *)spriv->gpio;
+
+ gpiochip_remove(&gpio->gpio_chip);
+ kfree(gpio);
+}
+#endif
+
static int pl2303_startup(struct usb_serial *serial)
{
struct pl2303_serial_private *spriv;
@@ -262,6 +453,15 @@ static int pl2303_startup(struct usb_serial *serial)
kfree(buf);
+ if (spriv->type->ngpio > 0) {
+ int ret;
+
+ ret = spriv->type->gpio_startup(serial);
+ if (ret) {
+ kfree(spriv);
+ return ret;
+ }
+ }
return 0;
}
@@ -269,6 +469,8 @@ static void pl2303_release(struct usb_serial *serial)
{
struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
+ if (spriv->type->ngpio > 0)
+ spriv->type->gpio_release(serial);
kfree(spriv);
}
--
1.8.5.5.dirty
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