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| author |   Inki Dae <inki.dae@samsung.com> | 2014-08-13 17:03:12 +0900 |
|---|---|---|
| committer |   Inki Dae <daeinki@gmail.com> | 2014-09-20 00:56:08 +0900 |
| commit | 78d3a8c6134fbe1fe048b13bddb8e7602affabaa (patch) | |
| tree | 6f5b8c23086bddffb3c41bc31d31c88ac106e47d /drivers/gpu/drm/exynos | |
| parent | drm/mipi-dsi: consider low power transmission (diff) | |
| download | linux-dev-78d3a8c6134fbe1fe048b13bddb8e7602affabaa.tar.xz linux-dev-78d3a8c6134fbe1fe048b13bddb8e7602affabaa.zip | |
drm/exynos: mipi-dsi: consider non-continuous clock mode
This patch adds non-continuous clock mode support
Clock mode on Clock Lane is continuous clock by default.
So if we want to transmit data in non-continuous clock mode
to reduce power consumption, then host driver should set
DSIM_CLKLANE_STOP bit. In this case, host controller turns off
HS clock between high speed transmissions.
For this, this patch adds a new bit, DSIM_CLKLANE_STOP, and makes
the host driver sets this bit only in case that dsi->mode_flags has
MIPI_DSI_CLOCK_NON_CONTINUOUS flag.
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Diffstat (limited to 'drivers/gpu/drm/exynos')
| -rw-r--r-- | drivers/gpu/drm/exynos/exynos_drm_dsi.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c index d3393098f424..670c2f9be31c 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c +++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c @@ -114,6 +114,8 @@ #define DSIM_SYNC_INFORM (1 << 27) #define DSIM_EOT_DISABLE (1 << 28) #define DSIM_MFLUSH_VS (1 << 29) +/* This flag is valid only for exynos3250/3472/4415/5260/5430 */ +#define DSIM_CLKLANE_STOP (1 << 30) /* DSIM_ESCMODE */ #define DSIM_TX_TRIGGER_RST (1 << 4) @@ -262,6 +264,7 @@ struct exynos_dsi_driver_data { unsigned int plltmr_reg; unsigned int has_freqband:1; + unsigned int has_clklane_stop:1; }; struct exynos_dsi { @@ -304,6 +307,7 @@ struct exynos_dsi { static struct exynos_dsi_driver_data exynos4_dsi_driver_data = { .plltmr_reg = 0x50, .has_freqband = 1, + .has_clklane_stop = 1, }; static struct exynos_dsi_driver_data exynos5_dsi_driver_data = { @@ -569,6 +573,7 @@ static void exynos_dsi_disable_clock(struct exynos_dsi *dsi) static int exynos_dsi_init_link(struct exynos_dsi *dsi) { + struct exynos_dsi_driver_data *driver_data = dsi->driver_data; int timeout; u32 reg; u32 lanes_mask; @@ -650,6 +655,20 @@ static int exynos_dsi_init_link(struct exynos_dsi *dsi) reg |= DSIM_LANE_EN(lanes_mask); writel(reg, dsi->reg_base + DSIM_CONFIG_REG); + /* + * Use non-continuous clock mode if the periparal wants and + * host controller supports + * + * In non-continous clock mode, host controller will turn off + * the HS clock between high-speed transmissions to reduce + * power consumption. + */ + if (driver_data->has_clklane_stop && + dsi->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) { + reg |= DSIM_CLKLANE_STOP; + writel(reg, dsi->reg_base + DSIM_CONFIG_REG); + } + /* Check clock and data lane state are stop state */ timeout = 100; do { |