drm/radeon/kms: take the pm mutex when using hw i2c
we need a constant sclk for i2c prescale. Also,
get the current sclk when calculating prescale rather
than using the default sclk.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon_i2c.c b/drivers/gpu/drm/radeon/radeon_i2c.c
index b47a561..272c45d 100644
--- a/drivers/gpu/drm/radeon/radeon_i2c.c
+++ b/drivers/gpu/drm/radeon/radeon_i2c.c
@@ -192,12 +192,16 @@
struct radeon_i2c_bus_rec *rec = &i2c->rec;
struct i2c_msg *p;
int i, j, k, ret = num;
- /* XXX: use get_engine_clock() to get the current sclk */
- u32 prescale = (((rdev->clock.default_sclk * 10)/(4 * 128 * 100) + 1) << 8) + 128;
+ u32 sclk, prescale;
u32 i2c_cntl_0, i2c_cntl_1, i2c_data;
u32 tmp, reg;
mutex_lock(&rdev->dc_hw_i2c_mutex);
+ /* take the pm lock since we need a constant sclk */
+ mutex_lock(&rdev->pm.mutex);
+
+ sclk = radeon_get_engine_clock(rdev);
+ prescale = (((sclk * 10)/(4 * 128 * 100) + 1) << 8) + 128;
reg = ((prescale << RADEON_I2C_PRESCALE_SHIFT) |
RADEON_I2C_START |
@@ -424,6 +428,7 @@
WREG32(RADEON_BIOS_6_SCRATCH, tmp);
}
+ mutex_unlock(&rdev->pm.mutex);
mutex_unlock(&rdev->dc_hw_i2c_mutex);
return ret;
@@ -441,12 +446,19 @@
struct i2c_msg *p;
int i2c_clock = 50;
int i, j, remaining, current_count, buffer_offset, ret = num;
- /* XXX: use get_engine_clock() to get the current sclk */
- u32 prescale;
+ u32 sclk, prescale;
u32 tmp, reg;
u32 saved1, saved2;
mutex_lock(&rdev->dc_hw_i2c_mutex);
+ /* take the pm lock since we need a constant sclk */
+ mutex_lock(&rdev->pm.mutex);
+
+ sclk = radeon_get_engine_clock(rdev);
+ if (rdev->family == CHIP_R520)
+ prescale = (127 << 8) + ((sclk * 10) / (4 * 127 * i2c_clock));
+ else
+ prescale = (((sclk * 10)/(4 * 128 * 100) + 1) << 8) + 128;
/* clear gpio mask bits */
tmp = RREG32(rec->mask_clk_reg);
@@ -500,11 +512,6 @@
goto done;
}
- if (rdev->family == CHIP_R520)
- prescale = (127 << 8) + ((rdev->clock.default_sclk * 10) / (4 * 127 * i2c_clock));
- else
- prescale = (((rdev->clock.default_sclk * 10)/(4 * 128 * 100) + 1) << 8) + 128;
-
reg = AVIVO_DC_I2C_START | AVIVO_DC_I2C_STOP | AVIVO_DC_I2C_EN;
switch (rec->mask_clk_reg) {
case AVIVO_DC_GPIO_DDC1_MASK:
@@ -662,6 +669,7 @@
tmp &= ~ATOM_S6_HW_I2C_BUSY_STATE;
WREG32(RADEON_BIOS_6_SCRATCH, tmp);
+ mutex_unlock(&rdev->pm.mutex);
mutex_unlock(&rdev->dc_hw_i2c_mutex);
return ret;