diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 213 |
1 files changed, 176 insertions, 37 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index f0fc3a0d37c8..f4c26c7826cd 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -21,6 +21,7 @@ #include <linux/uaccess.h> #include <linux/compat.h> #include <linux/anon_inodes.h> +#include <linux/file.h> #include <linux/kfifo.h> #include <linux/poll.h> #include <linux/timekeeping.h> @@ -333,6 +334,13 @@ struct linehandle_state { u32 numdescs; }; +#define GPIOHANDLE_REQUEST_VALID_FLAGS \ + (GPIOHANDLE_REQUEST_INPUT | \ + GPIOHANDLE_REQUEST_OUTPUT | \ + GPIOHANDLE_REQUEST_ACTIVE_LOW | \ + GPIOHANDLE_REQUEST_OPEN_DRAIN | \ + GPIOHANDLE_REQUEST_OPEN_SOURCE) + static long linehandle_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) { @@ -344,6 +352,8 @@ static long linehandle_ioctl(struct file *filep, unsigned int cmd, if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) { int val; + memset(&ghd, 0, sizeof(ghd)); + /* TODO: check if descriptors are really input */ for (i = 0; i < lh->numdescs; i++) { val = gpiod_get_value_cansleep(lh->descs[i]); @@ -414,6 +424,7 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip) { struct gpiohandle_request handlereq; struct linehandle_state *lh; + struct file *file; int fd, i, ret; if (copy_from_user(&handlereq, ip, sizeof(handlereq))) @@ -444,6 +455,17 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip) u32 lflags = handlereq.flags; struct gpio_desc *desc; + if (offset >= gdev->ngpio) { + ret = -EINVAL; + goto out_free_descs; + } + + /* Return an error if a unknown flag is set */ + if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) { + ret = -EINVAL; + goto out_free_descs; + } + desc = &gdev->descs[offset]; ret = gpiod_request(desc, lh->label); if (ret) @@ -479,26 +501,41 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip) i--; lh->numdescs = handlereq.lines; - fd = anon_inode_getfd("gpio-linehandle", - &linehandle_fileops, - lh, - O_RDONLY | O_CLOEXEC); + fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC); if (fd < 0) { ret = fd; goto out_free_descs; } + file = anon_inode_getfile("gpio-linehandle", + &linehandle_fileops, + lh, + O_RDONLY | O_CLOEXEC); + if (IS_ERR(file)) { + ret = PTR_ERR(file); + goto out_put_unused_fd; + } + handlereq.fd = fd; if (copy_to_user(ip, &handlereq, sizeof(handlereq))) { - ret = -EFAULT; - goto out_free_descs; + /* + * fput() will trigger the release() callback, so do not go onto + * the regular error cleanup path here. + */ + fput(file); + put_unused_fd(fd); + return -EFAULT; } + fd_install(fd, file); + dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n", lh->numdescs); return 0; +out_put_unused_fd: + put_unused_fd(fd); out_free_descs: for (; i >= 0; i--) gpiod_free(lh->descs[i]); @@ -536,6 +573,10 @@ struct lineevent_state { struct mutex read_lock; }; +#define GPIOEVENT_REQUEST_VALID_FLAGS \ + (GPIOEVENT_REQUEST_RISING_EDGE | \ + GPIOEVENT_REQUEST_FALLING_EDGE) + static unsigned int lineevent_poll(struct file *filep, struct poll_table_struct *wait) { @@ -623,6 +664,8 @@ static long lineevent_ioctl(struct file *filep, unsigned int cmd, if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) { int val; + memset(&ghd, 0, sizeof(ghd)); + val = gpiod_get_value_cansleep(le->desc); if (val < 0) return val; @@ -695,6 +738,7 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip) struct gpioevent_request eventreq; struct lineevent_state *le; struct gpio_desc *desc; + struct file *file; u32 offset; u32 lflags; u32 eflags; @@ -726,6 +770,18 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip) lflags = eventreq.handleflags; eflags = eventreq.eventflags; + if (offset >= gdev->ngpio) { + ret = -EINVAL; + goto out_free_label; + } + + /* Return an error if a unknown flag is set */ + if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) || + (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) { + ret = -EINVAL; + goto out_free_label; + } + /* This is just wrong: we don't look for events on output lines */ if (lflags & GPIOHANDLE_REQUEST_OUTPUT) { ret = -EINVAL; @@ -777,23 +833,38 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip) if (ret) goto out_free_desc; - fd = anon_inode_getfd("gpio-event", - &lineevent_fileops, - le, - O_RDONLY | O_CLOEXEC); + fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC); if (fd < 0) { ret = fd; goto out_free_irq; } + file = anon_inode_getfile("gpio-event", + &lineevent_fileops, + le, + O_RDONLY | O_CLOEXEC); + if (IS_ERR(file)) { + ret = PTR_ERR(file); + goto out_put_unused_fd; + } + eventreq.fd = fd; if (copy_to_user(ip, &eventreq, sizeof(eventreq))) { - ret = -EFAULT; - goto out_free_irq; + /* + * fput() will trigger the release() callback, so do not go onto + * the regular error cleanup path here. + */ + fput(file); + put_unused_fd(fd); + return -EFAULT; } + fd_install(fd, file); + return 0; +out_put_unused_fd: + put_unused_fd(fd); out_free_irq: free_irq(le->irq, le); out_free_desc: @@ -823,6 +894,8 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) if (cmd == GPIO_GET_CHIPINFO_IOCTL) { struct gpiochip_info chipinfo; + memset(&chipinfo, 0, sizeof(chipinfo)); + strncpy(chipinfo.name, dev_name(&gdev->dev), sizeof(chipinfo.name)); chipinfo.name[sizeof(chipinfo.name)-1] = '\0'; @@ -839,7 +912,7 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) if (copy_from_user(&lineinfo, ip, sizeof(lineinfo))) return -EFAULT; - if (lineinfo.line_offset > gdev->ngpio) + if (lineinfo.line_offset >= gdev->ngpio) return -EINVAL; desc = &gdev->descs[lineinfo.line_offset]; @@ -913,7 +986,8 @@ static int gpio_chrdev_open(struct inode *inode, struct file *filp) return -ENODEV; get_device(&gdev->dev); filp->private_data = gdev; - return 0; + + return nonseekable_open(inode, filp); } /** @@ -938,7 +1012,7 @@ static const struct file_operations gpio_fileops = { .release = gpio_chrdev_release, .open = gpio_chrdev_open, .owner = THIS_MODULE, - .llseek = noop_llseek, + .llseek = no_llseek, .unlocked_ioctl = gpio_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = gpio_ioctl_compat, @@ -1439,7 +1513,7 @@ static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip, } /** - * gpiochip_set_chained_irqchip() - sets a chained irqchip to a gpiochip + * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip * @gpiochip: the gpiochip to set the irqchip chain to * @irqchip: the irqchip to chain to the gpiochip * @parent_irq: the irq number corresponding to the parent IRQ for this @@ -1448,10 +1522,10 @@ static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip, * coming out of the gpiochip. If the interrupt is nested rather than * cascaded, pass NULL in this handler argument */ -void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, - struct irq_chip *irqchip, - int parent_irq, - irq_flow_handler_t parent_handler) +static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gpiochip, + struct irq_chip *irqchip, + int parent_irq, + irq_flow_handler_t parent_handler) { unsigned int offset; @@ -1475,7 +1549,7 @@ void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, irq_set_chained_handler_and_data(parent_irq, parent_handler, gpiochip); - gpiochip->irq_parent = parent_irq; + gpiochip->irq_chained_parent = parent_irq; } /* Set the parent IRQ for all affected IRQs */ @@ -1486,9 +1560,48 @@ void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, parent_irq); } } + +/** + * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip + * @gpiochip: the gpiochip to set the irqchip chain to + * @irqchip: the irqchip to chain to the gpiochip + * @parent_irq: the irq number corresponding to the parent IRQ for this + * chained irqchip + * @parent_handler: the parent interrupt handler for the accumulated IRQ + * coming out of the gpiochip. If the interrupt is nested rather than + * cascaded, pass NULL in this handler argument + */ +void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, + struct irq_chip *irqchip, + int parent_irq, + irq_flow_handler_t parent_handler) +{ + gpiochip_set_cascaded_irqchip(gpiochip, irqchip, parent_irq, + parent_handler); +} EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); /** + * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip + * @gpiochip: the gpiochip to set the irqchip nested handler to + * @irqchip: the irqchip to nest to the gpiochip + * @parent_irq: the irq number corresponding to the parent IRQ for this + * nested irqchip + */ +void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip, + struct irq_chip *irqchip, + int parent_irq) +{ + if (!gpiochip->irq_nested) { + chip_err(gpiochip, "tried to nest a chained gpiochip\n"); + return; + } + gpiochip_set_cascaded_irqchip(gpiochip, irqchip, parent_irq, + NULL); +} +EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip); + +/** * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip * @d: the irqdomain used by this irqchip * @irq: the global irq number used by this GPIO irqchip irq @@ -1510,8 +1623,8 @@ static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, */ irq_set_lockdep_class(irq, chip->lock_key); irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler); - /* Chips that can sleep need nested thread handlers */ - if (chip->can_sleep && !chip->irq_not_threaded) + /* Chips that use nested thread handlers have them marked */ + if (chip->irq_nested) irq_set_nested_thread(irq, 1); irq_set_noprobe(irq); @@ -1529,7 +1642,7 @@ static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) { struct gpio_chip *chip = d->host_data; - if (chip->can_sleep) + if (chip->irq_nested) irq_set_nested_thread(irq, 0); irq_set_chip_and_handler(irq, NULL, NULL); irq_set_chip_data(irq, NULL); @@ -1584,9 +1697,9 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) acpi_gpiochip_free_interrupts(gpiochip); - if (gpiochip->irq_parent) { - irq_set_chained_handler(gpiochip->irq_parent, NULL); - irq_set_handler_data(gpiochip->irq_parent, NULL); + if (gpiochip->irq_chained_parent) { + irq_set_chained_handler(gpiochip->irq_chained_parent, NULL); + irq_set_handler_data(gpiochip->irq_chained_parent, NULL); } /* Remove all IRQ mappings and delete the domain */ @@ -1610,7 +1723,7 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) } /** - * gpiochip_irqchip_add() - adds an irqchip to a gpiochip + * _gpiochip_irqchip_add() - adds an irqchip to a gpiochip * @gpiochip: the gpiochip to add the irqchip to * @irqchip: the irqchip to add to the gpiochip * @first_irq: if not dynamically assigned, the base (first) IRQ to @@ -1618,6 +1731,8 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) * @handler: the irq handler to use (often a predefined irq core function) * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE * to have the core avoid setting up any default type in the hardware. + * @nested: whether this is a nested irqchip calling handle_nested_irq() + * in its IRQ handler * @lock_key: lockdep class * * This function closely associates a certain irqchip with a certain @@ -1639,6 +1754,7 @@ int _gpiochip_irqchip_add(struct gpio_chip *gpiochip, unsigned int first_irq, irq_flow_handler_t handler, unsigned int type, + bool nested, struct lock_class_key *lock_key) { struct device_node *of_node; @@ -1653,6 +1769,7 @@ int _gpiochip_irqchip_add(struct gpio_chip *gpiochip, pr_err("missing gpiochip .dev parent pointer\n"); return -EINVAL; } + gpiochip->irq_nested = nested; of_node = gpiochip->parent->of_node; #ifdef CONFIG_OF_GPIO /* @@ -2150,6 +2267,7 @@ EXPORT_SYMBOL_GPL(gpiod_direction_input); static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) { struct gpio_chip *gc = desc->gdev->chip; + int val = !!value; int ret; /* GPIOs used for IRQs shall not be set as output */ @@ -2169,7 +2287,7 @@ static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) goto set_output_value; } /* Emulate open drain by not actively driving the line high */ - if (value) + if (val) return gpiod_direction_input(desc); } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) { @@ -2180,7 +2298,7 @@ static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) goto set_output_value; } /* Emulate open source by not actively driving the line low */ - if (!value) + if (!val) return gpiod_direction_input(desc); } else { /* Make sure to disable open drain/source hardware, if any */ @@ -2198,10 +2316,10 @@ set_output_value: return -EIO; } - ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), value); + ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val); if (!ret) set_bit(FLAG_IS_OUT, &desc->flags); - trace_gpio_value(desc_to_gpio(desc), 0, value); + trace_gpio_value(desc_to_gpio(desc), 0, val); trace_gpio_direction(desc_to_gpio(desc), 0, ret); return ret; } @@ -2241,6 +2359,8 @@ int gpiod_direction_output(struct gpio_desc *desc, int value) VALIDATE_DESC(desc); if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) value = !value; + else + value = !!value; return _gpiod_direction_output_raw(desc, value); } EXPORT_SYMBOL_GPL(gpiod_direction_output); @@ -2664,8 +2784,11 @@ int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset) if (IS_ERR(desc)) return PTR_ERR(desc); - /* Flush direction if something changed behind our back */ - if (chip->get_direction) { + /* + * If it's fast: flush the direction setting if something changed + * behind our back + */ + if (!chip->can_sleep && chip->get_direction) { int dir = chip->get_direction(chip, offset); if (dir) @@ -2682,6 +2805,15 @@ int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset) } set_bit(FLAG_USED_AS_IRQ, &desc->flags); + + /* + * If the consumer has not set up a label (such as when the + * IRQ is referenced from .to_irq()) we set up a label here + * so it is clear this is used as an interrupt. + */ + if (!desc->label) + desc_set_label(desc, "interrupt"); + return 0; } EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); @@ -2696,10 +2828,17 @@ EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); */ void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) { - if (offset >= chip->ngpio) + struct gpio_desc *desc; + + desc = gpiochip_get_desc(chip, offset); + if (IS_ERR(desc)) return; - clear_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags); + clear_bit(FLAG_USED_AS_IRQ, &desc->flags); + + /* If we only had this marking, erase it */ + if (desc->label && !strcmp(desc->label, "interrupt")) + desc_set_label(desc, NULL); } EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq); @@ -3094,7 +3233,7 @@ static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, /* Process flags */ if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) status = gpiod_direction_output(desc, - dflags & GPIOD_FLAGS_BIT_DIR_VAL); + !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL)); else status = gpiod_direction_input(desc); |