drm/amd/display: Flatten unnecessary i2c functions

[Why]
The dce_i2c_hw code contained four funtcions that were only
called in one place and did not have a clearly delineated
purpose.

[How]
Inline these functions, keeping the same functionality.

This is not a functional change.

The functions disable_i2c_hw_engine and release_engine_dce_hw were
pulled into their respective callers.

The most interesting part of this change is the acquire functions.
dce_i2c_hw_engine_acquire_engine was pulled into
dce_i2c_engine_acquire_hw, and dce_i2c_engine_acquire_hw was pulled
into acquire_i2c_hw_engine.

Some notes to show that this change is not functional:
-Failure conditions in any function resulted in a cascade of calls that
ended in a 'return NULL'.
Those are replaced with a direct 'return NULL'.

-The variable result is the one from dce_i2c_hw_engine_acquire_engine.
The boolean result used as part of return logic was removed.

-As the second half of dce_i2c_hw_engine_acquire_engine is only executed
if that function is returning true and therefore exiting the do-while
loop in dce_i2c_engine_acquire_hw, those lines were moved outside
of the loop.

Signed-off-by: David Francis <David.Francis@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_i2c_hw.c b/drivers/gpu/drm/amd/display/dc/dce/dce_i2c_hw.c
index 2800d3fa49da634bc9558ebb48780b401de1c6c0..40f2d6e0b122d5d7b1c5c2539926a9992b79cc79 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_i2c_hw.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_i2c_hw.c
@@ -36,12 +36,6 @@
 #define FN(reg_name, field_name) \
        dce_i2c_hw->shifts->field_name, dce_i2c_hw->masks->field_name
 
-static void disable_i2c_hw_engine(
-       struct dce_i2c_hw *dce_i2c_hw)
-{
-       REG_UPDATE_N(SETUP, 1, FN(SETUP, DC_I2C_DDC1_ENABLE), 0);
-}
-
 static void execute_transaction(
        struct dce_i2c_hw *dce_i2c_hw)
 {
@@ -348,60 +342,40 @@ static void release_engine(
                REG_UPDATE(DC_I2C_CONTROL, DC_I2C_SW_STATUS_RESET, 1);
        /* HW I2c engine - clock gating feature */
        if (!dce_i2c_hw->engine_keep_power_up_count)
-               disable_i2c_hw_engine(dce_i2c_hw);
+               REG_UPDATE_N(SETUP, 1, FN(SETUP, DC_I2C_DDC1_ENABLE), 0);
 
 }
 
-static void release_engine_dce_hw(
+struct dce_i2c_hw *acquire_i2c_hw_engine(
        struct resource_pool *pool,
-       struct dce_i2c_hw *dce_i2c_hw)
-{
-       pool->i2c_hw_buffer_in_use = false;
-
-       release_engine(dce_i2c_hw);
-       dal_ddc_close(dce_i2c_hw->ddc);
-
-       dce_i2c_hw->ddc = NULL;
-}
-
-bool dce_i2c_hw_engine_acquire_engine(
-       struct dce_i2c_hw *dce_i2c_hw,
        struct ddc *ddc)
 {
-
+       uint32_t counter = 0;
        enum gpio_result result;
        uint32_t current_speed;
+       struct dce_i2c_hw *dce_i2c_hw = NULL;
 
-       result = dal_ddc_open(ddc, GPIO_MODE_HARDWARE,
-               GPIO_DDC_CONFIG_TYPE_MODE_I2C);
-
-       if (result != GPIO_RESULT_OK)
-               return false;
-
-       dce_i2c_hw->ddc = ddc;
-
-
-       current_speed = get_speed(dce_i2c_hw);
+       if (!ddc)
+               return NULL;
 
-       if (current_speed)
-               dce_i2c_hw->original_speed = current_speed;
+       if (ddc->hw_info.hw_supported) {
+               enum gpio_ddc_line line = dal_ddc_get_line(ddc);
 
-       return true;
-}
+               if (line < pool->pipe_count)
+                       dce_i2c_hw = pool->hw_i2cs[line];
+       }
 
-bool dce_i2c_engine_acquire_hw(
-       struct dce_i2c_hw *dce_i2c_hw,
-       struct ddc *ddc_handle)
-{
+       if (!dce_i2c_hw)
+               return NULL;
 
-       uint32_t counter = 0;
-       bool result;
+       if (pool->i2c_hw_buffer_in_use)
+               return NULL;
 
        do {
-               result = dce_i2c_hw_engine_acquire_engine(
-                               dce_i2c_hw, ddc_handle);
+               result = dal_ddc_open(ddc, GPIO_MODE_HARDWARE,
+                       GPIO_DDC_CONFIG_TYPE_MODE_I2C);
 
-               if (result)
+               if (result == GPIO_RESULT_OK)
                        break;
 
                /* i2c_engine is busy by VBios, lets wait and retry */
@@ -411,45 +385,23 @@ bool dce_i2c_engine_acquire_hw(
                ++counter;
        } while (counter < 2);
 
-       if (result) {
-               if (!setup_engine(dce_i2c_hw)) {
-                       release_engine(dce_i2c_hw);
-                       result = false;
-               }
-       }
-
-       return result;
-}
-
-struct dce_i2c_hw *acquire_i2c_hw_engine(
-       struct resource_pool *pool,
-       struct ddc *ddc)
-{
-
-       struct dce_i2c_hw *engine = NULL;
-
-       if (!ddc)
+       if (result != GPIO_RESULT_OK)
                return NULL;
 
-       if (ddc->hw_info.hw_supported) {
-               enum gpio_ddc_line line = dal_ddc_get_line(ddc);
-
-               if (line < pool->pipe_count)
-                       engine = pool->hw_i2cs[line];
-       }
+       dce_i2c_hw->ddc = ddc;
 
-       if (!engine)
-               return NULL;
+       current_speed = get_speed(dce_i2c_hw);
 
+       if (current_speed)
+               dce_i2c_hw->original_speed = current_speed;
 
-       if (!pool->i2c_hw_buffer_in_use &&
-                       dce_i2c_engine_acquire_hw(engine, ddc)) {
-               pool->i2c_hw_buffer_in_use = true;
-               return engine;
+       if (!setup_engine(dce_i2c_hw)) {
+               release_engine(dce_i2c_hw);
+               return NULL;
        }
 
-
-       return NULL;
+       pool->i2c_hw_buffer_in_use = true;
+       return dce_i2c_hw;
 }
 
 enum i2c_channel_operation_result dce_i2c_hw_engine_wait_on_operation_result(
@@ -619,7 +571,12 @@ bool dce_i2c_submit_command_hw(
                ++index_of_payload;
        }
 
-       release_engine_dce_hw(pool, dce_i2c_hw);
+       pool->i2c_hw_buffer_in_use = false;
+
+       release_engine(dce_i2c_hw);
+       dal_ddc_close(dce_i2c_hw->ddc);
+
+       dce_i2c_hw->ddc = NULL;
 
        return result;
 }