From 90caf1dfe9efb727874bcafd30fefb0807cb7670 Mon Sep 17 00:00:00 2001 From: Orlando Chamberlain Date: Fri, 3 Mar 2023 22:28:40 +1100 Subject: [PATCH 1/8] platform/x86: apple-gmux: use first bit to check switch state On T2 Macs with MMIO gmux, when GMUX_PORT_SWITCH_DISPLAY is read, it can have values of 2, 3, 4, and 5. Odd values correspond to the discrete gpu, and even values correspond to the integrated gpu. The current logic is that only 2 corresponds to IGD, but this doesn't work for T2 Macs. Instead, check the first bit to determine the connected gpu. As T2 Macs with gmux only can switch the internal display, it is untested if this change (or a similar change) would be applicable to GMUX_PORT_SWITCH_DDC and GMUX_PORT_SWITCH_EXTERNAL. Reviewed-by: Hans de Goede Signed-off-by: Orlando Chamberlain Link: https://lore.kernel.org/r/20230303112842.3094-2-orlandoch.dev@gmail.com Signed-off-by: Hans de Goede --- drivers/platform/x86/apple-gmux.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index 9333f82cfa8a..ec99e05e532c 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -346,10 +346,10 @@ 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; From 96ec2d9868c4afd3cea17f4ee18b84ccc1cde20f Mon Sep 17 00:00:00 2001 From: Orlando Chamberlain Date: Fri, 3 Mar 2023 22:28:41 +1100 Subject: [PATCH 2/8] platform/x86: apple-gmux: refactor gmux types Add apple_gmux_config struct containing operations and data specific to each mux type. This is in preparation for adding a third, MMIO based, gmux type. Reviewed-by: Hans de Goede Signed-off-by: Orlando Chamberlain Link: https://lore.kernel.org/r/20230303112842.3094-3-orlandoch.dev@gmail.com Signed-off-by: Hans de Goede --- drivers/platform/x86/apple-gmux.c | 93 ++++++++++++++++++++----------- include/linux/apple-gmux.h | 18 ++++-- 2 files changed, 74 insertions(+), 37 deletions(-) diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index ec99e05e532c..36208e93d745 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 @@ -43,10 +44,12 @@ * http://www.renesas.com/products/mpumcu/h8s/h8s2100/h8s2113/index.jsp */ +struct apple_gmux_config; + struct apple_gmux_data { unsigned long iostart; unsigned long iolen; - bool indexed; + const struct apple_gmux_config *config; struct mutex index_lock; struct backlight_device *bdev; @@ -64,6 +67,18 @@ struct apple_gmux_data { 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 @@ -195,35 +210,23 @@ static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port, 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); } /** @@ -463,19 +466,43 @@ 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" +}; + /** * DOC: Interrupt * @@ -565,13 +592,13 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) 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 +608,16 @@ 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_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 +628,7 @@ 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; + 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; @@ -604,7 +639,7 @@ 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; @@ -694,12 +729,8 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) * * 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; diff --git a/include/linux/apple-gmux.h b/include/linux/apple-gmux.h index 1f68b49bcd68..147dc1c52e08 100644 --- a/include/linux/apple-gmux.h +++ b/include/linux/apple-gmux.h @@ -36,6 +36,11 @@ #define GMUX_MIN_IO_LEN (GMUX_PORT_BRIGHTNESS + 4) +enum apple_gmux_type { + APPLE_GMUX_TYPE_PIO, + APPLE_GMUX_TYPE_INDEXED, +}; + #if IS_ENABLED(CONFIG_APPLE_GMUX) static inline bool apple_gmux_is_indexed(unsigned long iostart) { @@ -65,13 +70,13 @@ 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) { @@ -99,13 +104,14 @@ static inline bool apple_gmux_detect(struct pnp_dev *pnp_dev, bool *indexed_ret) 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 (apple_gmux_is_indexed(res->start)) + type = APPLE_GMUX_TYPE_INDEXED; + else goto out; } - if (indexed_ret) - *indexed_ret = indexed; + if (type_ret) + *type_ret = type; ret = true; out: From 0c18184de990e63f708b090bcb9fc6c0fbc427cd Mon Sep 17 00:00:00 2001 From: Orlando Chamberlain Date: Fri, 3 Mar 2023 22:28:42 +1100 Subject: [PATCH 3/8] platform/x86: apple-gmux: support MMIO gmux on T2 Macs In some newer dual gpu MacBooks, the T2 Coprocessor functions as the gmux, and the Intel side can interract with this new gmux type through MMIO. Add support for these gmux controllers to the apple-gmux driver. We start using the GMSP(0) acpi method on these gmux's when clearing interrupts, as this prevents a flood of status=0 interrupts that can't be cleared. It's unknown if this helps or hinders older gmux types, so it isn't enabled for those. Interestingly, the ACPI table only allocates 8 bytes for GMUX, but we actually need 16, and as such we request 16 with request_mem_region. Reading and writing from ports: 16 bytes from 0xfe0b0200 are used. 0x0 to 0x4 are where data to read appears, and where data to write goes. Writing to 0xe sets the gmux port being accessed, and writing to 0xf sends commands. These commands are 0x40 & data_length for write, and data_length for read, where data_length is 1, 2 or 4. Once byte base+0xf is 0, the command is done. Issues: As with other retina models, we can't switch DDC lines so switching at runtime doesn't work if the inactive gpu driver already disabled eDP due to it not being connected when that driver loaded. Additionally, turning on the dgpu back on on the MacBookPro16,1 does not work. Reviewed-by: Hans de Goede Signed-off-by: Orlando Chamberlain Link: https://lore.kernel.org/r/20230303112842.3094-4-orlandoch.dev@gmail.com Signed-off-by: Hans de Goede --- drivers/platform/x86/apple-gmux.c | 170 +++++++++++++++++++++++++++--- include/linux/apple-gmux.h | 56 +++++++--- 2 files changed, 200 insertions(+), 26 deletions(-) diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index 36208e93d745..59c4ee8109dd 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -28,25 +28,35 @@ * 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; const struct apple_gmux_config *config; @@ -208,6 +218,79 @@ 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) { return gmux_data->config->read8(gmux_data, port); @@ -236,8 +319,8 @@ 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 @@ -301,8 +384,8 @@ 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 @@ -503,14 +586,42 @@ static const struct apple_gmux_config apple_gmux_index = { .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) @@ -537,6 +648,9 @@ 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) @@ -609,6 +723,25 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) 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); @@ -628,6 +761,7 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) goto err_free; } +get_version: if (gmux_data->config->read_version_as_u32) { version = gmux_read32(gmux_data, GMUX_PORT_VERSION_MAJOR); ver_major = (version >> 24) & 0xff; @@ -658,7 +792,7 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) gmux_data, &gmux_bl_ops, &props); if (IS_ERR(bdev)) { ret = PTR_ERR(bdev); - goto err_release; + goto err_unmap; } gmux_data->bdev = bdev; @@ -725,7 +859,7 @@ 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. */ @@ -750,8 +884,14 @@ 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; @@ -772,7 +912,11 @@ 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); diff --git a/include/linux/apple-gmux.h b/include/linux/apple-gmux.h index 147dc1c52e08..272f63f8fd7c 100644 --- a/include/linux/apple-gmux.h +++ b/include/linux/apple-gmux.h @@ -34,11 +34,18 @@ #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) @@ -57,6 +64,24 @@ 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 * @@ -93,19 +118,24 @@ static inline bool apple_gmux_detect(struct pnp_dev *pnp_dev, enum apple_gmux_ty } 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) { - if (apple_gmux_is_indexed(res->start)) - type = APPLE_GMUX_TYPE_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; } From f863fac1b15f77fc3c115f5afbd535983bb961a1 Mon Sep 17 00:00:00 2001 From: Orlando Chamberlain Date: Fri, 3 Mar 2023 22:28:43 +1100 Subject: [PATCH 4/8] platform/x86: apple-gmux: add debugfs interface Allow reading and writing gmux ports from userspace. For example: echo 4 > /sys/kernel/debug/apple_gmux/selected_port cat /sys/kernel/debug/apple_gmux/selected_port_data | xxd -p Will show the gmux version information (00000005 in this case) Reviewed-by: Hans de Goede Signed-off-by: Orlando Chamberlain Link: https://lore.kernel.org/r/20230303112842.3094-5-orlandoch.dev@gmail.com Signed-off-by: Hans de Goede --- drivers/platform/x86/apple-gmux.c | 82 +++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index 59c4ee8109dd..757fd71c900f 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -22,6 +22,7 @@ #include #include #include +#include #include /** @@ -73,6 +74,10 @@ 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; @@ -670,6 +675,81 @@ 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; + int ret; + + if (*ppos) + return -EINVAL; + + if (count == 1) { + u8 data; + + ret = copy_from_user(&data, userbuf, 1); + if (ret) + return ret; + gmux_write8(gmux_data, gmux_data->selected_port, data); + } else if (count == 4) { + u32 data; + + ret = copy_from_user(&data, userbuf, 4); + if (ret) + return ret; + 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); @@ -870,6 +950,7 @@ get_version: goto err_register_handler; } + gmux_init_debugfs(gmux_data); return 0; err_register_handler: @@ -901,6 +982,7 @@ 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) { From d2e6832147998ba12c810cf88862126f6fae9b0a Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 7 Mar 2023 12:38:13 +0100 Subject: [PATCH 5/8] platform/x86: apple-gmux: Add acpi_video_get_backlight_type() check Make apple-gmux backlight registration honor the acpi_backlight=... kernel commandline option which is used to select the backlight control method on x86/ACPI devices. Reported-and-tested-by: Aditya Garg Link: https://lore.kernel.org/platform-driver-x86/BM1PR01MB0931B467250831916F7C55B3B8A59@BM1PR01MB0931.INDPRD01.PROD.OUTLOOK.COM/ Signed-off-by: Hans de Goede Link: https://lore.kernel.org/r/20230307113813.359743-1-hdegoede@redhat.com --- drivers/platform/x86/apple-gmux.c | 59 +++++++++++++++++-------------- 1 file changed, 33 insertions(+), 26 deletions(-) diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index 757fd71c900f..ad81cb1df8f2 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -23,6 +23,7 @@ #include #include #include +#include #include /** @@ -781,8 +782,9 @@ 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; @@ -859,34 +861,39 @@ get_version: 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_unmap; + 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); + + /* + * 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->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); From ad3d0ee8dca5fa4a656057e20f9605bbe7ff067c Mon Sep 17 00:00:00 2001 From: Orlando Chamberlain Date: Thu, 9 Mar 2023 21:43:54 +1100 Subject: [PATCH 6/8] platform/x86: apple-gmux: Update apple_gmux_detect documentation Commit fc83fbc80e1a ("platform/x86: apple-gmux: refactor gmux types") neglected to update the documentation of apple_gmux_detect's arguments. Update the documentation to reflect that commit's changes. include/linux/apple-gmux.h:99: warning: Function parameter or member 'type_ret' not described in 'apple_gmux_detect' include/linux/apple-gmux.h:99: warning: Excess function parameter 'indexed_ret' description in 'apple_gmux_detect' Reported-by: Stephen Rothwell Link: https://lore.kernel.org/lkml/20230309122822.77435e33@canb.auug.org.au/ Fixes: fc83fbc80e1a ("platform/x86: apple-gmux: refactor gmux types") Signed-off-by: Orlando Chamberlain Link: https://lore.kernel.org/r/20230309104353.10905-1-orlandoch.dev@gmail.com Reviewed-by: Hans de Goede Signed-off-by: Hans de Goede --- include/linux/apple-gmux.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/apple-gmux.h b/include/linux/apple-gmux.h index 272f63f8fd7c..a7a7d430024b 100644 --- a/include/linux/apple-gmux.h +++ b/include/linux/apple-gmux.h @@ -86,7 +86,7 @@ static inline bool apple_gmux_is_mmio(unsigned long iostart) * 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 From f0f2903de50418899a5e5dcecf2906da44a7a05e Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Fri, 10 Mar 2023 15:31:13 +0300 Subject: [PATCH 7/8] platform/x86: apple-gmux: return -EFAULT if copy fails The copy_to/from_user() functions return the number of bytes remaining to be copied, but we want to return -EFAULT to the user. Fixes: ce3fef2eb235 ("platform/x86: apple-gmux: add debugfs interface") Signed-off-by: Dan Carpenter Reviewed-by: Orlando Chamberlain Link: https://lore.kernel.org/r/0bdfa8c2-cb22-4bec-8773-584060613043@kili.mountain Reviewed-by: Hans de Goede Signed-off-by: Hans de Goede --- drivers/platform/x86/apple-gmux.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index ad81cb1df8f2..8aa81a3517b1 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -694,7 +694,6 @@ 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; - int ret; if (*ppos) return -EINVAL; @@ -702,16 +701,16 @@ static ssize_t gmux_selected_port_data_write(struct file *file, if (count == 1) { u8 data; - ret = copy_from_user(&data, userbuf, 1); - if (ret) - return ret; + if (copy_from_user(&data, userbuf, 1)) + return -EFAULT; + gmux_write8(gmux_data, gmux_data->selected_port, data); } else if (count == 4) { u32 data; - ret = copy_from_user(&data, userbuf, 4); - if (ret) - return ret; + if (copy_from_user(&data, userbuf, 4)) + return -EFAULT; + gmux_write32(gmux_data, gmux_data->selected_port, data); } else return -EINVAL; From 3608a2cd818a8d97bd3d4dc32f6c0afaf09b15ec Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 7 Mar 2023 13:05:40 +0100 Subject: [PATCH 8/8] backlight: apple_bl: Use acpi_video_get_backlight_type() On some MacBooks both the apple_bl and the apple-gmux backlight drivers may be able to export a /sys/class/backlight device. To avoid having 2 backlight devices for one LCD panel until now the apple-gmux driver has been calling apple_bl_unregister() to move the apple_bl backlight device out of the way when it loads. Similar problems exist on other x86 laptops and all backlight drivers which may be used on x86 laptops have moved to using acpi_video_get_backlight_type() to determine whether they should load or not. Switch apple_bl to this model too, so that it is consistent with all the other x86 backlight drivers. Besides code-simplification and consistency this has 2 other benefits: 1) It removes a race during boot where userspace will briefly see an apple_bl backlight and then have it disappear again, leading to e.g.: https://bbs.archlinux.org/viewtopic.php?id=269920 2) This allows user to switch between the drivers by passing acpi_backlight=apple_gmux or acpi_backlight=vendor on the kernel commandline. Signed-off-by: Hans de Goede Reviewed-by: Daniel Thompson Acked-by: Lee Jones Link: https://lore.kernel.org/r/20230307120540.389920-1-hdegoede@redhat.com --- drivers/platform/x86/Kconfig | 1 - drivers/platform/x86/apple-gmux.c | 11 ----------- drivers/video/backlight/Kconfig | 1 + drivers/video/backlight/apple_bl.c | 31 ++++++++++-------------------- include/linux/apple_bl.h | 27 -------------------------- 5 files changed, 11 insertions(+), 60 deletions(-) delete mode 100644 include/linux/apple_bl.h diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index ec7c2b4e1721..1b3189d6e8d2 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -213,7 +213,6 @@ 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 8aa81a3517b1..4c311e1dedad 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -16,7 +16,6 @@ #include #include #include -#include #include #include #include @@ -883,14 +882,6 @@ get_version: 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; @@ -1007,8 +998,6 @@ static void gmux_remove(struct pnp_dev *pnp) 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_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 */