From 62d2f23e8bce3e7da4db53928e810fc8a474ce70 Mon Sep 17 00:00:00 2001 From: Mattia Dongili Date: Mon, 9 May 2011 10:20:29 -0400 Subject: [PATCH] sony-laptop: limit brightness range to DSDT provided ones The new style brightness control provides an operating range of 9 values (seems consistent over a large number of models sharing the same brightness control methods). Read and use the minimum and maximum values to limit the backlight interface between those boundaries. Signed-off-by: Mattia Dongili Signed-off-by: Matthew Garrett --- drivers/platform/x86/sony-laptop.c | 127 ++++++++++++++++++++++++++++++------- 1 file changed, 103 insertions(+), 24 deletions(-) diff --git a/drivers/platform/x86/sony-laptop.c b/drivers/platform/x86/sony-laptop.c index 9d80ae4..6fe8cd6 100644 --- a/drivers/platform/x86/sony-laptop.c +++ b/drivers/platform/x86/sony-laptop.c @@ -934,6 +934,14 @@ static ssize_t sony_nc_sysfs_store(struct device *dev, /* * Backlight device */ +struct sony_backlight_props { + struct backlight_device *dev; + int handle; + u8 offset; + u8 maxlvl; +}; +struct sony_backlight_props sony_bl_props; + static int sony_backlight_update_status(struct backlight_device *bd) { return acpi_callsetfunc(sony_nc_acpi_handle, "SBRT", @@ -954,19 +962,23 @@ static int sony_nc_get_brightness_ng(struct backlight_device *bd) { int result; int *handle = (int *)bl_get_data(bd); + struct sony_backlight_props *sdev = + (struct sony_backlight_props *)bl_get_data(bd); - sony_call_snc_handle(*handle, 0x0200, &result); + sony_call_snc_handle(sdev->handle, 0x0200, &result); - return result & 0xff; + return (result & 0xff) - sdev->offset; } static int sony_nc_update_status_ng(struct backlight_device *bd) { int value, result; int *handle = (int *)bl_get_data(bd); + struct sony_backlight_props *sdev = + (struct sony_backlight_props *)bl_get_data(bd); - value = bd->props.brightness; - if (sony_call_snc_handle(*handle, 0x0100 | (value << 16), &result)) + value = bd->props.brightness + sdev->offset; + if (sony_call_snc_handle(sdev->handle, 0x0100 | (value << 16), &result)) return -EIO; return value; @@ -982,8 +994,6 @@ static const struct backlight_ops sony_backlight_ng_ops = { .update_status = sony_nc_update_status_ng, .get_brightness = sony_nc_get_brightness_ng, }; -static int backlight_ng_handle; -static struct backlight_device *sony_backlight_device; /* * New SNC-only Vaios event mapping to driver known keys @@ -1550,6 +1560,75 @@ static void sony_nc_kbd_backlight_resume(void) &ignore); } +static void sony_nc_backlight_ng_read_limits(int handle, + struct sony_backlight_props *props) +{ + int offset; + acpi_status status; + u8 brlvl, i; + u8 min = 0xff, max = 0x00; + struct acpi_object_list params; + union acpi_object in_obj; + union acpi_object *lvl_enum; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + + props->handle = handle; + props->offset = 0; + props->maxlvl = 0xff; + + offset = sony_find_snc_handle(handle); + if (offset < 0) + return; + + /* try to read the boundaries from ACPI tables, if we fail the above + * defaults should be reasonable + */ + params.count = 1; + params.pointer = &in_obj; + in_obj.type = ACPI_TYPE_INTEGER; + in_obj.integer.value = offset; + status = acpi_evaluate_object(sony_nc_acpi_handle, "SN06", ¶ms, + &buffer); + if (ACPI_FAILURE(status)) + return; + + lvl_enum = (union acpi_object *) buffer.pointer; + if (!lvl_enum) { + pr_err("No SN06 return object."); + return; + } + if (lvl_enum->type != ACPI_TYPE_BUFFER) { + pr_err("Invalid SN06 return object 0x%.2x\n", + lvl_enum->type); + goto out_invalid; + } + + /* the buffer lists brightness levels available, brightness levels are + * from 0 to 8 in the array, other values are used by ALS control. + */ + for (i = 0; i < 9 && i < lvl_enum->buffer.length; i++) { + + brlvl = *(lvl_enum->buffer.pointer + i); + dprintk("Brightness level: %d\n", brlvl); + + if (!brlvl) + break; + + if (brlvl > max) + max = brlvl; + if (brlvl < min) + min = brlvl; + } + props->offset = min; + props->maxlvl = max; + dprintk("Brightness levels: min=%d max=%d\n", props->offset, + props->maxlvl); + +out_invalid: + kfree(buffer.pointer); + return; +} + static void sony_nc_backlight_setup(void) { acpi_handle unused; @@ -1558,14 +1637,14 @@ static void sony_nc_backlight_setup(void) struct backlight_properties props; if (sony_find_snc_handle(0x12f) != -1) { - backlight_ng_handle = 0x12f; ops = &sony_backlight_ng_ops; - max_brightness = 0xff; + sony_nc_backlight_ng_read_limits(0x12f, &sony_bl_props); + max_brightness = sony_bl_props.maxlvl - sony_bl_props.offset; } else if (sony_find_snc_handle(0x137) != -1) { - backlight_ng_handle = 0x137; ops = &sony_backlight_ng_ops; - max_brightness = 0xff; + sony_nc_backlight_ng_read_limits(0x137, &sony_bl_props); + max_brightness = sony_bl_props.maxlvl - sony_bl_props.offset; } else if (ACPI_SUCCESS(acpi_get_handle(sony_nc_acpi_handle, "GBRT", &unused))) { @@ -1578,22 +1657,22 @@ static void sony_nc_backlight_setup(void) memset(&props, 0, sizeof(struct backlight_properties)); props.type = BACKLIGHT_PLATFORM; props.max_brightness = max_brightness; - sony_backlight_device = backlight_device_register("sony", NULL, - &backlight_ng_handle, - ops, &props); + sony_bl_props.dev = backlight_device_register("sony", NULL, + &sony_bl_props, + ops, &props); - if (IS_ERR(sony_backlight_device)) { - pr_warning(DRV_PFX "unable to register backlight device\n"); - sony_backlight_device = NULL; + if (IS_ERR(sony_bl_props.dev)) { + pr_warn(DRV_PFX "unable to register backlight device\n"); + sony_bl_props.dev = NULL; } else - sony_backlight_device->props.brightness = - ops->get_brightness(sony_backlight_device); + sony_bl_props.dev->props.brightness = + ops->get_brightness(sony_bl_props.dev); } static void sony_nc_backlight_cleanup(void) { - if (sony_backlight_device) - backlight_device_unregister(sony_backlight_device); + if (sony_bl_props.dev) + backlight_device_unregister(sony_bl_props.dev); } static int sony_nc_add(struct acpi_device *device) @@ -2591,7 +2670,7 @@ static long sonypi_misc_ioctl(struct file *fp, unsigned int cmd, mutex_lock(&spic_dev.lock); switch (cmd) { case SONYPI_IOCGBRT: - if (sony_backlight_device == NULL) { + if (sony_bl_props.dev == NULL) { ret = -EIO; break; } @@ -2604,7 +2683,7 @@ static long sonypi_misc_ioctl(struct file *fp, unsigned int cmd, ret = -EFAULT; break; case SONYPI_IOCSBRT: - if (sony_backlight_device == NULL) { + if (sony_bl_props.dev == NULL) { ret = -EIO; break; } @@ -2618,8 +2697,8 @@ static long sonypi_misc_ioctl(struct file *fp, unsigned int cmd, break; } /* sync the backlight device status */ - sony_backlight_device->props.brightness = - sony_backlight_get_brightness(sony_backlight_device); + sony_bl_props.dev->props.brightness = + sony_backlight_get_brightness(sony_bl_props.dev); break; case SONYPI_IOCGBAT1CAP: if (ec_read16(SONYPI_BAT1_FULL, &val16)) { -- cgit v1.1