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authorMatthew Garrett <mjg@redhat.com>2012-08-09 13:45:01 -0400
committerMatthew Garrett <mjg@redhat.com>2012-08-17 17:34:39 -0400
commit96ff705638e3d61b1e45a047c0f9f3bb622fa32f (patch)
tree258fb8b63a724f710d445edfa7ef528ed14e5cd5 /drivers
parent7e30ed6bdd91ae73c34fc37b57fcccc8640641f9 (diff)
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 <mjg@redhat.com> Cc: Bernhard Froemel <froemel@vmars.tuwien.ac.at> Cc: Seth Forshee <seth.forshee@canonical.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/platform/x86/apple-gmux.c179
1 files changed, 165 insertions, 14 deletions
diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c
index c9db50729f6..0d140e1879e 100644
--- a/drivers/platform/x86/apple-gmux.c
+++ b/drivers/platform/x86/apple-gmux.c
@@ -18,12 +18,15 @@
#include <linux/pnp.h>
#include <linux/apple_bl.h>
#include <linux/slab.h>
+#include <linux/delay.h>
#include <acpi/video.h>
#include <asm/io.h>
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);