diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index d2619e7025c7..aa8df8d4aee9 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -206,7 +206,6 @@ config APPLE_GMUX depends on ACPI && PCI depends on PNP depends on BACKLIGHT_CLASS_DEVICE - depends on BACKLIGHT_APPLE=n || BACKLIGHT_APPLE help This driver provides support for the gmux device found on many Apple laptops, which controls the display mux for the hybrid diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index 9333f82cfa8a..4c311e1dedad 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -5,6 +5,7 @@ * Copyright (C) Canonical Ltd. * Copyright (C) 2010-2012 Andreas Heider * Copyright (C) 2015 Lukas Wunner + * Copyright (C) 2023 Orlando Chamberlain */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt @@ -15,38 +16,51 @@ #include #include #include -#include #include #include #include #include #include +#include +#include #include /** * DOC: Overview * * gmux is a microcontroller built into the MacBook Pro to support dual GPUs: - * A `Lattice XP2`_ on pre-retinas, a `Renesas R4F2113`_ on retinas. + * A `Lattice XP2`_ on pre-retinas, a `Renesas R4F2113`_ on pre-T2 retinas. + * + * On T2 Macbooks, the gmux is part of the T2 Coprocessor's SMC. The SMC has + * an I2C connection to a `NXP PCAL6524` GPIO expander, which enables/disables + * the voltage regulators of the discrete GPU, drives the display panel power, + * and has a GPIO to switch the eDP mux. The Intel CPU can interact with + * gmux through MMIO, similar to how the main SMC interface is controlled. * * (The MacPro6,1 2013 also has a gmux, however it is unclear why since it has * dual GPUs but no built-in display.) * * gmux is connected to the LPC bus of the southbridge. Its I/O ports are * accessed differently depending on the microcontroller: Driver functions - * to access a pre-retina gmux are infixed ``_pio_``, those for a retina gmux - * are infixed ``_index_``. + * to access a pre-retina gmux are infixed ``_pio_``, those for a pre-T2 + * retina gmux are infixed ``_index_``, and those on T2 Macs are infixed + * with ``_mmio_``. * * .. _Lattice XP2: * http://www.latticesemi.com/en/Products/FPGAandCPLD/LatticeXP2.aspx * .. _Renesas R4F2113: * http://www.renesas.com/products/mpumcu/h8s/h8s2100/h8s2113/index.jsp + * .. _NXP PCAL6524: + * https://www.nxp.com/docs/en/data-sheet/PCAL6524.pdf */ +struct apple_gmux_config; + struct apple_gmux_data { + u8 *__iomem iomem_base; unsigned long iostart; unsigned long iolen; - bool indexed; + const struct apple_gmux_config *config; struct mutex index_lock; struct backlight_device *bdev; @@ -60,10 +74,26 @@ struct apple_gmux_data { enum vga_switcheroo_client_id switch_state_external; enum vga_switcheroo_state power_state; struct completion powerchange_done; + + /* debugfs data */ + u8 selected_port; + struct dentry *debug_dentry; }; static struct apple_gmux_data *apple_gmux_data; +struct apple_gmux_config { + u8 (*read8)(struct apple_gmux_data *gmux_data, int port); + void (*write8)(struct apple_gmux_data *gmux_data, int port, u8 val); + u32 (*read32)(struct apple_gmux_data *gmux_data, int port); + void (*write32)(struct apple_gmux_data *gmux_data, int port, u32 val); + const struct vga_switcheroo_handler *gmux_handler; + enum vga_switcheroo_handler_flags_t handler_flags; + unsigned long resource_type; + bool read_version_as_u32; + char *name; +}; + #define GMUX_INTERRUPT_ENABLE 0xff #define GMUX_INTERRUPT_DISABLE 0x00 @@ -193,37 +223,98 @@ static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port, mutex_unlock(&gmux_data->index_lock); } +static int gmux_mmio_wait(struct apple_gmux_data *gmux_data) +{ + int i = 200; + u8 gwr = ioread8(gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + + while (i && gwr) { + gwr = ioread8(gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + udelay(100); + i--; + } + + return !!i; +} + +static u8 gmux_mmio_read8(struct apple_gmux_data *gmux_data, int port) +{ + u8 val; + + mutex_lock(&gmux_data->index_lock); + gmux_mmio_wait(gmux_data); + iowrite8((port & 0xff), gmux_data->iomem_base + GMUX_MMIO_PORT_SELECT); + iowrite8(GMUX_MMIO_READ | sizeof(val), + gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + gmux_mmio_wait(gmux_data); + val = ioread8(gmux_data->iomem_base); + mutex_unlock(&gmux_data->index_lock); + + return val; +} + +static void gmux_mmio_write8(struct apple_gmux_data *gmux_data, int port, + u8 val) +{ + mutex_lock(&gmux_data->index_lock); + gmux_mmio_wait(gmux_data); + iowrite8(val, gmux_data->iomem_base); + + iowrite8(port & 0xff, gmux_data->iomem_base + GMUX_MMIO_PORT_SELECT); + iowrite8(GMUX_MMIO_WRITE | sizeof(val), + gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + + gmux_mmio_wait(gmux_data); + mutex_unlock(&gmux_data->index_lock); +} + +static u32 gmux_mmio_read32(struct apple_gmux_data *gmux_data, int port) +{ + u32 val; + + mutex_lock(&gmux_data->index_lock); + gmux_mmio_wait(gmux_data); + iowrite8((port & 0xff), gmux_data->iomem_base + GMUX_MMIO_PORT_SELECT); + iowrite8(GMUX_MMIO_READ | sizeof(val), + gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + gmux_mmio_wait(gmux_data); + val = be32_to_cpu(ioread32(gmux_data->iomem_base)); + mutex_unlock(&gmux_data->index_lock); + + return val; +} + +static void gmux_mmio_write32(struct apple_gmux_data *gmux_data, int port, + u32 val) +{ + mutex_lock(&gmux_data->index_lock); + iowrite32(cpu_to_be32(val), gmux_data->iomem_base); + iowrite8(port & 0xff, gmux_data->iomem_base + GMUX_MMIO_PORT_SELECT); + iowrite8(GMUX_MMIO_WRITE | sizeof(val), + gmux_data->iomem_base + GMUX_MMIO_COMMAND_SEND); + gmux_mmio_wait(gmux_data); + mutex_unlock(&gmux_data->index_lock); +} + static u8 gmux_read8(struct apple_gmux_data *gmux_data, int port) { - if (gmux_data->indexed) - return gmux_index_read8(gmux_data, port); - else - return gmux_pio_read8(gmux_data, port); + return gmux_data->config->read8(gmux_data, port); } static void gmux_write8(struct apple_gmux_data *gmux_data, int port, u8 val) { - if (gmux_data->indexed) - gmux_index_write8(gmux_data, port, val); - else - gmux_pio_write8(gmux_data, port, val); + return gmux_data->config->write8(gmux_data, port, val); } static u32 gmux_read32(struct apple_gmux_data *gmux_data, int port) { - if (gmux_data->indexed) - return gmux_index_read32(gmux_data, port); - else - return gmux_pio_read32(gmux_data, port); + return gmux_data->config->read32(gmux_data, port); } static void gmux_write32(struct apple_gmux_data *gmux_data, int port, u32 val) { - if (gmux_data->indexed) - gmux_index_write32(gmux_data, port, val); - else - gmux_pio_write32(gmux_data, port, val); + return gmux_data->config->write32(gmux_data, port, val); } /** @@ -233,8 +324,8 @@ static void gmux_write32(struct apple_gmux_data *gmux_data, int port, * the GPU. On dual GPU MacBook Pros by contrast, either GPU may be suspended * to conserve energy. Hence the PWM signal needs to be generated by a separate * backlight driver which is controlled by gmux. The earliest generation - * MBP5 2008/09 uses a `TI LP8543`_ backlight driver. All newer models - * use a `TI LP8545`_. + * MBP5 2008/09 uses a `TI LP8543`_ backlight driver. Newer models + * use a `TI LP8545`_ or a TI LP8548. * * .. _TI LP8543: https://www.ti.com/lit/ds/symlink/lp8543.pdf * .. _TI LP8545: https://www.ti.com/lit/ds/symlink/lp8545.pdf @@ -298,8 +389,8 @@ static const struct backlight_ops gmux_bl_ops = { * connecting it either to the discrete GPU or the Thunderbolt controller. * Oddly enough, while the full port is no longer switchable, AUX and HPD * are still switchable by way of an `NXP CBTL03062`_ (on pre-retinas - * MBP8 2011 and MBP9 2012) or two `TI TS3DS10224`_ (on retinas) under the - * control of gmux. Since the integrated GPU is missing the main link, + * MBP8 2011 and MBP9 2012) or two `TI TS3DS10224`_ (on pre-t2 retinas) under + * the control of gmux. Since the integrated GPU is missing the main link, * external displays appear to it as phantoms which fail to link-train. * * gmux receives the HPD signal of all display connectors and sends an @@ -346,10 +437,10 @@ static void gmux_read_switch_state(struct apple_gmux_data *gmux_data) else gmux_data->switch_state_ddc = VGA_SWITCHEROO_DIS; - if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DISPLAY) == 2) - gmux_data->switch_state_display = VGA_SWITCHEROO_IGD; - else + if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DISPLAY) & 1) gmux_data->switch_state_display = VGA_SWITCHEROO_DIS; + else + gmux_data->switch_state_display = VGA_SWITCHEROO_IGD; if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_EXTERNAL) == 2) gmux_data->switch_state_external = VGA_SWITCHEROO_IGD; @@ -463,27 +554,79 @@ static enum vga_switcheroo_client_id gmux_get_client_id(struct pci_dev *pdev) return VGA_SWITCHEROO_DIS; } -static const struct vga_switcheroo_handler gmux_handler_indexed = { +static const struct vga_switcheroo_handler gmux_handler_no_ddc = { .switchto = gmux_switchto, .power_state = gmux_set_power_state, .get_client_id = gmux_get_client_id, }; -static const struct vga_switcheroo_handler gmux_handler_classic = { +static const struct vga_switcheroo_handler gmux_handler_ddc = { .switchto = gmux_switchto, .switch_ddc = gmux_switch_ddc, .power_state = gmux_set_power_state, .get_client_id = gmux_get_client_id, }; +static const struct apple_gmux_config apple_gmux_pio = { + .read8 = &gmux_pio_read8, + .write8 = &gmux_pio_write8, + .read32 = &gmux_pio_read32, + .write32 = &gmux_pio_write32, + .gmux_handler = &gmux_handler_ddc, + .handler_flags = VGA_SWITCHEROO_CAN_SWITCH_DDC, + .resource_type = IORESOURCE_IO, + .read_version_as_u32 = false, + .name = "classic" +}; + +static const struct apple_gmux_config apple_gmux_index = { + .read8 = &gmux_index_read8, + .write8 = &gmux_index_write8, + .read32 = &gmux_index_read32, + .write32 = &gmux_index_write32, + .gmux_handler = &gmux_handler_no_ddc, + .handler_flags = VGA_SWITCHEROO_NEEDS_EDP_CONFIG, + .resource_type = IORESOURCE_IO, + .read_version_as_u32 = true, + .name = "indexed" +}; + +static const struct apple_gmux_config apple_gmux_mmio = { + .read8 = &gmux_mmio_read8, + .write8 = &gmux_mmio_write8, + .read32 = &gmux_mmio_read32, + .write32 = &gmux_mmio_write32, + .gmux_handler = &gmux_handler_no_ddc, + .handler_flags = VGA_SWITCHEROO_NEEDS_EDP_CONFIG, + .resource_type = IORESOURCE_MEM, + .read_version_as_u32 = true, + .name = "T2" +}; + + /** * DOC: Interrupt * * gmux is also connected to a GPIO pin of the southbridge and thereby is able - * to trigger an ACPI GPE. On the MBP5 2008/09 it's GPIO pin 22 of the Nvidia - * MCP79, on all following generations it's GPIO pin 6 of the Intel PCH. + * to trigger an ACPI GPE. ACPI name GMGP holds this GPIO pin's number. On the + * MBP5 2008/09 it's GPIO pin 22 of the Nvidia MCP79, on following generations + * it's GPIO pin 6 of the Intel PCH, on MMIO gmux's it's pin 21. + * * The GPE merely signals that an interrupt occurred, the actual type of event * is identified by reading a gmux register. + * + * In addition to the GMGP name, gmux's ACPI device also has two methods GMSP + * and GMLV. GMLV likely means "GMUX Level", and reads the value of the GPIO, + * while GMSP likely means "GMUX Set Polarity", and seems to write to the GPIO's + * value. On newer Macbooks (This was introduced with or sometime before the + * MacBookPro14,3), the ACPI GPE method differentiates between the OS type: On + * Darwin, only a notification is signaled, whereas on other OSes, the GPIO's + * value is read and then inverted. + * + * Because Linux masquerades as Darwin, it ends up in the notification-only code + * path. On MMIO gmux's, this seems to lead to us being unable to clear interrupts, + * unless we call GMSP(0). Without this, there is a flood of status=0 interrupts + * that can't be cleared. This issue seems to be unique to MMIO gmux's. */ static inline void gmux_disable_interrupts(struct apple_gmux_data *gmux_data) @@ -510,6 +653,9 @@ static void gmux_clear_interrupts(struct apple_gmux_data *gmux_data) /* to clear interrupts write back current status */ status = gmux_interrupt_get_status(gmux_data); gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status); + /* Prevent flood of status=0 interrupts */ + if (gmux_data->config == &apple_gmux_mmio) + acpi_execute_simple_method(gmux_data->dhandle, "GMSP", 0); } static void gmux_notify_handler(acpi_handle device, u32 value, void *context) @@ -529,6 +675,80 @@ static void gmux_notify_handler(acpi_handle device, u32 value, void *context) complete(&gmux_data->powerchange_done); } +/** + * DOC: Debugfs Interface + * + * gmux ports can be accessed from userspace as a debugfs interface. For example: + * + * # echo 4 > /sys/kernel/debug/apple_gmux/selected_port + * # cat /sys/kernel/debug/apple_gmux/selected_port_data | xxd -p + * 00000005 + * + * Reads 4 bytes from port 4 (GMUX_PORT_VERSION_MAJOR). + * + * 1 and 4 byte writes are also allowed. + */ + +static ssize_t gmux_selected_port_data_write(struct file *file, + const char __user *userbuf, size_t count, loff_t *ppos) +{ + struct apple_gmux_data *gmux_data = file->private_data; + + if (*ppos) + return -EINVAL; + + if (count == 1) { + u8 data; + + if (copy_from_user(&data, userbuf, 1)) + return -EFAULT; + + gmux_write8(gmux_data, gmux_data->selected_port, data); + } else if (count == 4) { + u32 data; + + if (copy_from_user(&data, userbuf, 4)) + return -EFAULT; + + gmux_write32(gmux_data, gmux_data->selected_port, data); + } else + return -EINVAL; + + return count; +} + +static ssize_t gmux_selected_port_data_read(struct file *file, + char __user *userbuf, size_t count, loff_t *ppos) +{ + struct apple_gmux_data *gmux_data = file->private_data; + u32 data; + + data = gmux_read32(gmux_data, gmux_data->selected_port); + + return simple_read_from_buffer(userbuf, count, ppos, &data, sizeof(data)); +} + +static const struct file_operations gmux_port_data_ops = { + .open = simple_open, + .write = gmux_selected_port_data_write, + .read = gmux_selected_port_data_read +}; + +static void gmux_init_debugfs(struct apple_gmux_data *gmux_data) +{ + gmux_data->debug_dentry = debugfs_create_dir(KBUILD_MODNAME, NULL); + + debugfs_create_u8("selected_port", 0644, gmux_data->debug_dentry, + &gmux_data->selected_port); + debugfs_create_file("selected_port_data", 0644, gmux_data->debug_dentry, + gmux_data, &gmux_port_data_ops); +} + +static void gmux_fini_debugfs(struct apple_gmux_data *gmux_data) +{ + debugfs_remove_recursive(gmux_data->debug_dentry); +} + static int gmux_suspend(struct device *dev) { struct pnp_dev *pnp = to_pnp_dev(dev); @@ -560,18 +780,19 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) struct apple_gmux_data *gmux_data; struct resource *res; struct backlight_properties props; - struct backlight_device *bdev; + struct backlight_device *bdev = NULL; u8 ver_major, ver_minor, ver_release; + bool register_bdev = true; int ret = -ENXIO; acpi_status status; unsigned long long gpe; - bool indexed = false; + enum apple_gmux_type type; u32 version; if (apple_gmux_data) return -EBUSY; - if (!apple_gmux_detect(pnp, &indexed)) { + if (!apple_gmux_detect(pnp, &type)) { pr_info("gmux device not present\n"); return -ENODEV; } @@ -581,6 +802,35 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) return -ENOMEM; pnp_set_drvdata(pnp, gmux_data); + switch (type) { + case APPLE_GMUX_TYPE_MMIO: + gmux_data->config = &apple_gmux_mmio; + mutex_init(&gmux_data->index_lock); + + res = pnp_get_resource(pnp, IORESOURCE_MEM, 0); + gmux_data->iostart = res->start; + /* Although the ACPI table only allocates 8 bytes, we need 16. */ + gmux_data->iolen = 16; + if (!request_mem_region(gmux_data->iostart, gmux_data->iolen, + "Apple gmux")) { + pr_err("gmux I/O already in use\n"); + goto err_free; + } + gmux_data->iomem_base = ioremap(gmux_data->iostart, gmux_data->iolen); + if (!gmux_data->iomem_base) { + pr_err("couldn't remap gmux mmio region"); + goto err_release; + } + goto get_version; + case APPLE_GMUX_TYPE_INDEXED: + gmux_data->config = &apple_gmux_index; + mutex_init(&gmux_data->index_lock); + break; + case APPLE_GMUX_TYPE_PIO: + gmux_data->config = &apple_gmux_pio; + break; + } + res = pnp_get_resource(pnp, IORESOURCE_IO, 0); gmux_data->iostart = res->start; gmux_data->iolen = resource_size(res); @@ -591,9 +841,8 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) goto err_free; } - if (indexed) { - mutex_init(&gmux_data->index_lock); - gmux_data->indexed = true; +get_version: + if (gmux_data->config->read_version_as_u32) { version = gmux_read32(gmux_data, GMUX_PORT_VERSION_MAJOR); ver_major = (version >> 24) & 0xff; ver_minor = (version >> 16) & 0xff; @@ -604,40 +853,37 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) ver_release = gmux_read8(gmux_data, GMUX_PORT_VERSION_RELEASE); } pr_info("Found gmux version %d.%d.%d [%s]\n", ver_major, ver_minor, - ver_release, (gmux_data->indexed ? "indexed" : "classic")); + ver_release, gmux_data->config->name); memset(&props, 0, sizeof(props)); props.type = BACKLIGHT_PLATFORM; props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS); - /* - * Currently it's assumed that the maximum brightness is less than - * 2^24 for compatibility with old gmux versions. Cap the max - * brightness at this value, but print a warning if the hardware - * reports something higher so that it can be fixed. - */ - if (WARN_ON(props.max_brightness > GMUX_MAX_BRIGHTNESS)) - props.max_brightness = GMUX_MAX_BRIGHTNESS; +#if IS_REACHABLE(CONFIG_ACPI_VIDEO) + register_bdev = acpi_video_get_backlight_type() == acpi_backlight_apple_gmux; +#endif + if (register_bdev) { + /* + * Currently it's assumed that the maximum brightness is less than + * 2^24 for compatibility with old gmux versions. Cap the max + * brightness at this value, but print a warning if the hardware + * reports something higher so that it can be fixed. + */ + if (WARN_ON(props.max_brightness > GMUX_MAX_BRIGHTNESS)) + props.max_brightness = GMUX_MAX_BRIGHTNESS; - bdev = backlight_device_register("gmux_backlight", &pnp->dev, - gmux_data, &gmux_bl_ops, &props); - if (IS_ERR(bdev)) { - ret = PTR_ERR(bdev); - goto err_release; + bdev = backlight_device_register("gmux_backlight", &pnp->dev, + gmux_data, &gmux_bl_ops, &props); + if (IS_ERR(bdev)) { + ret = PTR_ERR(bdev); + goto err_unmap; + } + + gmux_data->bdev = bdev; + bdev->props.brightness = gmux_get_brightness(bdev); + backlight_update_status(bdev); } - gmux_data->bdev = bdev; - bdev->props.brightness = gmux_get_brightness(bdev); - backlight_update_status(bdev); - - /* - * The backlight situation on Macs is complicated. If the gmux is - * present it's the best choice, because it always works for - * backlight control and supports more levels than other options. - * Disable the other backlight choices. - */ - apple_bl_unregister(); - gmux_data->power_state = VGA_SWITCHEROO_ON; gmux_data->dhandle = ACPI_HANDLE(&pnp->dev); @@ -690,21 +936,18 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) /* * Retina MacBook Pros cannot switch the panel's AUX separately * and need eDP pre-calibration. They are distinguishable from - * pre-retinas by having an "indexed" gmux. + * pre-retinas by having an "indexed" or "T2" gmux. * * Pre-retina MacBook Pros can switch the panel's DDC separately. */ - if (gmux_data->indexed) - ret = vga_switcheroo_register_handler(&gmux_handler_indexed, - VGA_SWITCHEROO_NEEDS_EDP_CONFIG); - else - ret = vga_switcheroo_register_handler(&gmux_handler_classic, - VGA_SWITCHEROO_CAN_SWITCH_DDC); + ret = vga_switcheroo_register_handler(gmux_data->config->gmux_handler, + gmux_data->config->handler_flags); if (ret) { pr_err("Failed to register vga_switcheroo handler\n"); goto err_register_handler; } + gmux_init_debugfs(gmux_data); return 0; err_register_handler: @@ -719,8 +962,14 @@ err_enable_gpe: &gmux_notify_handler); err_notify: backlight_device_unregister(bdev); +err_unmap: + if (gmux_data->iomem_base) + iounmap(gmux_data->iomem_base); err_release: - release_region(gmux_data->iostart, gmux_data->iolen); + if (gmux_data->config->resource_type == IORESOURCE_MEM) + release_mem_region(gmux_data->iostart, gmux_data->iolen); + else + release_region(gmux_data->iostart, gmux_data->iolen); err_free: kfree(gmux_data); return ret; @@ -730,6 +979,7 @@ static void gmux_remove(struct pnp_dev *pnp) { struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp); + gmux_fini_debugfs(gmux_data); vga_switcheroo_unregister_handler(); gmux_disable_interrupts(gmux_data); if (gmux_data->gpe >= 0) { @@ -741,11 +991,13 @@ static void gmux_remove(struct pnp_dev *pnp) backlight_device_unregister(gmux_data->bdev); - release_region(gmux_data->iostart, gmux_data->iolen); + if (gmux_data->iomem_base) { + iounmap(gmux_data->iomem_base); + release_mem_region(gmux_data->iostart, gmux_data->iolen); + } else + release_region(gmux_data->iostart, gmux_data->iolen); apple_gmux_data = NULL; kfree(gmux_data); - - apple_bl_register(); } static const struct pnp_device_id gmux_device_ids[] = { diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index 4c33e971c0f0..51387b1ef012 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -285,6 +285,7 @@ config BACKLIGHT_MT6370 config BACKLIGHT_APPLE tristate "Apple Backlight Driver" depends on X86 && ACPI + depends on ACPI_VIDEO=n || ACPI_VIDEO help If you have an Intel-based Apple say Y to enable a driver for its backlight. diff --git a/drivers/video/backlight/apple_bl.c b/drivers/video/backlight/apple_bl.c index e9e7acb577bf..aaa824437a2a 100644 --- a/drivers/video/backlight/apple_bl.c +++ b/drivers/video/backlight/apple_bl.c @@ -24,7 +24,7 @@ #include #include #include -#include +#include static struct backlight_device *apple_backlight_device; @@ -215,32 +215,21 @@ static struct acpi_driver apple_bl_driver = { }, }; -static atomic_t apple_bl_registered = ATOMIC_INIT(0); - -int apple_bl_register(void) -{ - if (atomic_xchg(&apple_bl_registered, 1) == 0) - return acpi_bus_register_driver(&apple_bl_driver); - - return 0; -} -EXPORT_SYMBOL_GPL(apple_bl_register); - -void apple_bl_unregister(void) -{ - if (atomic_xchg(&apple_bl_registered, 0) == 1) - acpi_bus_unregister_driver(&apple_bl_driver); -} -EXPORT_SYMBOL_GPL(apple_bl_unregister); - static int __init apple_bl_init(void) { - return apple_bl_register(); + /* + * Use ACPI video detection code to see if this driver should register + * or if another driver, e.g. the apple-gmux driver should be used. + */ + if (acpi_video_get_backlight_type() != acpi_backlight_vendor) + return -ENODEV; + + return acpi_bus_register_driver(&apple_bl_driver); } static void __exit apple_bl_exit(void) { - apple_bl_unregister(); + acpi_bus_unregister_driver(&apple_bl_driver); } module_init(apple_bl_init); diff --git a/include/linux/apple-gmux.h b/include/linux/apple-gmux.h index 1f68b49bcd68..a7a7d430024b 100644 --- a/include/linux/apple-gmux.h +++ b/include/linux/apple-gmux.h @@ -34,8 +34,20 @@ #define GMUX_PORT_READ 0xd0 #define GMUX_PORT_WRITE 0xd4 +#define GMUX_MMIO_PORT_SELECT 0x0e +#define GMUX_MMIO_COMMAND_SEND 0x0f + +#define GMUX_MMIO_READ 0x00 +#define GMUX_MMIO_WRITE 0x40 + #define GMUX_MIN_IO_LEN (GMUX_PORT_BRIGHTNESS + 4) +enum apple_gmux_type { + APPLE_GMUX_TYPE_PIO, + APPLE_GMUX_TYPE_INDEXED, + APPLE_GMUX_TYPE_MMIO, +}; + #if IS_ENABLED(CONFIG_APPLE_GMUX) static inline bool apple_gmux_is_indexed(unsigned long iostart) { @@ -52,11 +64,29 @@ static inline bool apple_gmux_is_indexed(unsigned long iostart) return false; } +static inline bool apple_gmux_is_mmio(unsigned long iostart) +{ + u8 *__iomem iomem_base = ioremap(iostart, 16); + u8 val; + + if (!iomem_base) + return false; + + /* + * If this is 0xff, then gmux must not be present, as the gmux would + * reset it to 0x00, or it would be one of 0x1, 0x4, 0x41, 0x44 if a + * command is currently being processed. + */ + val = ioread8(iomem_base + GMUX_MMIO_COMMAND_SEND); + iounmap(iomem_base); + return (val != 0xff); +} + /** * apple_gmux_detect() - detect if gmux is built into the machine * * @pnp_dev: Device to probe or NULL to use the first matching device - * @indexed_ret: Returns (by reference) if the gmux is indexed or not + * @type_ret: Returns (by reference) the apple_gmux_type of the device * * Detect if a supported gmux device is present by actually probing it. * This avoids the false positives returned on some models by @@ -65,13 +95,13 @@ static inline bool apple_gmux_is_indexed(unsigned long iostart) * Return: %true if a supported gmux ACPI device is detected and the kernel * was configured with CONFIG_APPLE_GMUX, %false otherwise. */ -static inline bool apple_gmux_detect(struct pnp_dev *pnp_dev, bool *indexed_ret) +static inline bool apple_gmux_detect(struct pnp_dev *pnp_dev, enum apple_gmux_type *type_ret) { u8 ver_major, ver_minor, ver_release; struct device *dev = NULL; struct acpi_device *adev; struct resource *res; - bool indexed = false; + enum apple_gmux_type type = APPLE_GMUX_TYPE_PIO; bool ret = false; if (!pnp_dev) { @@ -88,24 +118,30 @@ static inline bool apple_gmux_detect(struct pnp_dev *pnp_dev, bool *indexed_ret) } res = pnp_get_resource(pnp_dev, IORESOURCE_IO, 0); - if (!res || resource_size(res) < GMUX_MIN_IO_LEN) - goto out; - - /* - * Invalid version information may indicate either that the gmux - * device isn't present or that it's a new one that uses indexed io. - */ - ver_major = inb(res->start + GMUX_PORT_VERSION_MAJOR); - ver_minor = inb(res->start + GMUX_PORT_VERSION_MINOR); - ver_release = inb(res->start + GMUX_PORT_VERSION_RELEASE); - if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) { - indexed = apple_gmux_is_indexed(res->start); - if (!indexed) + if (res && resource_size(res) >= GMUX_MIN_IO_LEN) { + /* + * Invalid version information may indicate either that the gmux + * device isn't present or that it's a new one that uses indexed io. + */ + ver_major = inb(res->start + GMUX_PORT_VERSION_MAJOR); + ver_minor = inb(res->start + GMUX_PORT_VERSION_MINOR); + ver_release = inb(res->start + GMUX_PORT_VERSION_RELEASE); + if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) { + if (apple_gmux_is_indexed(res->start)) + type = APPLE_GMUX_TYPE_INDEXED; + else + goto out; + } + } else { + res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0); + if (res && apple_gmux_is_mmio(res->start)) + type = APPLE_GMUX_TYPE_MMIO; + else goto out; } - if (indexed_ret) - *indexed_ret = indexed; + if (type_ret) + *type_ret = type; ret = true; out: diff --git a/include/linux/apple_bl.h b/include/linux/apple_bl.h deleted file mode 100644 index 445af2e3cc21..000000000000 --- a/include/linux/apple_bl.h +++ /dev/null @@ -1,27 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * apple_bl exported symbols - */ - -#ifndef _LINUX_APPLE_BL_H -#define _LINUX_APPLE_BL_H - -#if defined(CONFIG_BACKLIGHT_APPLE) || defined(CONFIG_BACKLIGHT_APPLE_MODULE) - -extern int apple_bl_register(void); -extern void apple_bl_unregister(void); - -#else /* !CONFIG_BACKLIGHT_APPLE */ - -static inline int apple_bl_register(void) -{ - return 0; -} - -static inline void apple_bl_unregister(void) -{ -} - -#endif /* !CONFIG_BACKLIGHT_APPLE */ - -#endif /* _LINUX_APPLE_BL_H */