From 96ff705638e3d61b1e45a047c0f9f3bb622fa32f Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Thu, 9 Aug 2012 13:45:01 -0400 Subject: [PATCH] apple_gmux: Add support for newer hardware New gmux devices have a different method for accessing the registers. Update the driver to cope. Incorporates feedback from Bernhard Froemel. Signed-off-by: Matthew Garrett Cc: Bernhard Froemel Cc: Seth Forshee --- drivers/platform/x86/apple-gmux.c | 179 +++++++++++++++++++++++++++--- 1 file changed, 165 insertions(+), 14 deletions(-) diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c index c9db50729f6f..0d140e1879e7 100644 --- a/drivers/platform/x86/apple-gmux.c +++ b/drivers/platform/x86/apple-gmux.c @@ -18,12 +18,15 @@ #include #include #include +#include #include #include struct apple_gmux_data { unsigned long iostart; unsigned long iolen; + bool indexed; + struct mutex index_lock; struct backlight_device *bdev; }; @@ -45,6 +48,9 @@ struct apple_gmux_data { #define GMUX_PORT_DISCRETE_POWER 0x50 #define GMUX_PORT_MAX_BRIGHTNESS 0x70 #define GMUX_PORT_BRIGHTNESS 0x74 +#define GMUX_PORT_VALUE 0xc2 +#define GMUX_PORT_READ 0xd0 +#define GMUX_PORT_WRITE 0xd4 #define GMUX_MIN_IO_LEN (GMUX_PORT_BRIGHTNESS + 4) @@ -59,24 +65,24 @@ struct apple_gmux_data { #define GMUX_BRIGHTNESS_MASK 0x00ffffff #define GMUX_MAX_BRIGHTNESS GMUX_BRIGHTNESS_MASK -static inline u8 gmux_read8(struct apple_gmux_data *gmux_data, int port) +static u8 gmux_pio_read8(struct apple_gmux_data *gmux_data, int port) { return inb(gmux_data->iostart + port); } -static inline void gmux_write8(struct apple_gmux_data *gmux_data, int port, +static void gmux_pio_write8(struct apple_gmux_data *gmux_data, int port, u8 val) { outb(val, gmux_data->iostart + port); } -static inline u32 gmux_read32(struct apple_gmux_data *gmux_data, int port) +static u32 gmux_pio_read32(struct apple_gmux_data *gmux_data, int port) { return inl(gmux_data->iostart + port); } -static inline u32 gmux_write32(struct apple_gmux_data *gmux_data, int port, - u32 val) +static void gmux_pio_write32(struct apple_gmux_data *gmux_data, int port, + u32 val) { int i; u8 tmpval; @@ -87,6 +93,144 @@ static inline u32 gmux_write32(struct apple_gmux_data *gmux_data, int port, } } +static int gmux_index_wait_ready(struct apple_gmux_data *gmux_data) +{ + int i = 200; + u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); + + while (i && (gwr & 0x01)) { + inb(gmux_data->iostart + GMUX_PORT_READ); + gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); + udelay(100); + i--; + } + + return !!i; +} + +static int gmux_index_wait_complete(struct apple_gmux_data *gmux_data) +{ + int i = 200; + u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); + + while (i && !(gwr & 0x01)) { + gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); + udelay(100); + i--; + } + + if (gwr & 0x01) + inb(gmux_data->iostart + GMUX_PORT_READ); + + return !!i; +} + +static u8 gmux_index_read8(struct apple_gmux_data *gmux_data, int port) +{ + u8 val; + + mutex_lock(&gmux_data->index_lock); + outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ); + gmux_index_wait_ready(gmux_data); + val = inb(gmux_data->iostart + GMUX_PORT_VALUE); + mutex_unlock(&gmux_data->index_lock); + + return val; +} + +static void gmux_index_write8(struct apple_gmux_data *gmux_data, int port, + u8 val) +{ + mutex_lock(&gmux_data->index_lock); + outb(val, gmux_data->iostart + GMUX_PORT_VALUE); + gmux_index_wait_ready(gmux_data); + outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE); + gmux_index_wait_complete(gmux_data); + mutex_unlock(&gmux_data->index_lock); +} + +static u32 gmux_index_read32(struct apple_gmux_data *gmux_data, int port) +{ + u32 val; + + mutex_lock(&gmux_data->index_lock); + outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ); + gmux_index_wait_ready(gmux_data); + val = inl(gmux_data->iostart + GMUX_PORT_VALUE); + mutex_unlock(&gmux_data->index_lock); + + return val; +} + +static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port, + u32 val) +{ + int i; + u8 tmpval; + + mutex_lock(&gmux_data->index_lock); + + for (i = 0; i < 4; i++) { + tmpval = (val >> (i * 8)) & 0xff; + outb(tmpval, gmux_data->iostart + GMUX_PORT_VALUE + i); + } + + gmux_index_wait_ready(gmux_data); + outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE); + gmux_index_wait_complete(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); +} + +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); +} + +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); +} + +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); +} + +static bool gmux_is_indexed(struct apple_gmux_data *gmux_data) +{ + u16 val; + + outb(0xaa, gmux_data->iostart + 0xcc); + outb(0x55, gmux_data->iostart + 0xcd); + outb(0x00, gmux_data->iostart + 0xce); + + val = inb(gmux_data->iostart + 0xcc) | + (inb(gmux_data->iostart + 0xcd) << 8); + + if (val == 0x55aa) + return true; + + return false; +} + static int gmux_get_brightness(struct backlight_device *bd) { struct apple_gmux_data *gmux_data = bl_get_data(bd); @@ -150,22 +294,29 @@ static int __devinit gmux_probe(struct pnp_dev *pnp, } /* - * On some machines the gmux is in ACPI even thought the machine - * doesn't really have a gmux. Check for invalid version information - * to detect this. + * 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 = gmux_read8(gmux_data, GMUX_PORT_VERSION_MAJOR); ver_minor = gmux_read8(gmux_data, GMUX_PORT_VERSION_MINOR); ver_release = gmux_read8(gmux_data, GMUX_PORT_VERSION_RELEASE); if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) { - pr_info("gmux device not present\n"); - ret = -ENODEV; - goto err_release; + if (gmux_is_indexed(gmux_data)) { + mutex_init(&gmux_data->index_lock); + gmux_data->indexed = true; + } else { + pr_info("gmux device not present\n"); + ret = -ENODEV; + goto err_release; + } + pr_info("Found indexed gmux\n"); + } else { + pr_info("Found gmux version %d.%d.%d\n", ver_major, ver_minor, + ver_release); } - pr_info("Found gmux version %d.%d.%d\n", ver_major, ver_minor, - ver_release); - memset(&props, 0, sizeof(props)); props.type = BACKLIGHT_PLATFORM; props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS); -- 2.20.1