drivers/gpu/drm/amd/display/dc/dce/dce_panel_cntl.c
Source file repositories/reference/linux-study-clean/drivers/gpu/drm/amd/display/dc/dce/dce_panel_cntl.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/gpu/drm/amd/display/dc/dce/dce_panel_cntl.c- Extension
.c- Size
- 9560 bytes
- Lines
- 295
- Domain
- Driver Families
- Bucket
- drivers/gpu
- Inferred role
- Driver Families: implementation source
- Status
- source implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
reg_helper.hcore_types.hdc_dmub_srv.hpanel_cntl.hdce_panel_cntl.hatom.h
Detected Declarations
function filesfunction dce_panel_cntl_hw_initfunction dce_is_panel_backlight_onfunction dce_is_panel_powered_onfunction dce_store_backlight_levelfunction dce_driver_set_backlightfunction dce_panel_cntl_destroyfunction dce_panel_cntl_construct
Annotated Snippet
#include "reg_helper.h"
#include "core_types.h"
#include "dc_dmub_srv.h"
#include "panel_cntl.h"
#include "dce_panel_cntl.h"
#include "atom.h"
#define TO_DCE_PANEL_CNTL(panel_cntl)\
container_of(panel_cntl, struct dce_panel_cntl, base)
#define CTX \
dce_panel_cntl->base.ctx
#define DC_LOGGER \
dce_panel_cntl->base.ctx->logger
#define REG(reg)\
dce_panel_cntl->regs->reg
#undef FN
#define FN(reg_name, field_name) \
dce_panel_cntl->shift->field_name, dce_panel_cntl->mask->field_name
static unsigned int dce_get_16_bit_backlight_from_pwm(struct panel_cntl *panel_cntl)
{
uint64_t current_backlight;
uint32_t bl_period, bl_int_count;
uint32_t bl_pwm, fractional_duty_cycle_en;
uint32_t bl_period_mask, bl_pwm_mask;
struct dce_panel_cntl *dce_panel_cntl = TO_DCE_PANEL_CNTL(panel_cntl);
REG_READ(BL_PWM_PERIOD_CNTL);
REG_GET(BL_PWM_PERIOD_CNTL, BL_PWM_PERIOD, &bl_period);
REG_GET(BL_PWM_PERIOD_CNTL, BL_PWM_PERIOD_BITCNT, &bl_int_count);
REG_READ(BL_PWM_CNTL);
REG_GET(BL_PWM_CNTL, BL_ACTIVE_INT_FRAC_CNT, (uint32_t *)(&bl_pwm));
REG_GET(BL_PWM_CNTL, BL_PWM_FRACTIONAL_EN, &fractional_duty_cycle_en);
if (bl_int_count == 0)
bl_int_count = 16;
bl_period_mask = (1 << bl_int_count) - 1;
bl_period &= bl_period_mask;
bl_pwm_mask = bl_period_mask << (16 - bl_int_count);
if (fractional_duty_cycle_en == 0)
bl_pwm &= bl_pwm_mask;
else
bl_pwm &= 0xFFFF;
current_backlight = (uint64_t)bl_pwm << (1 + bl_int_count);
if (bl_period == 0)
bl_period = 0xFFFF;
current_backlight = div_u64(current_backlight, bl_period);
current_backlight = (current_backlight + 1) >> 1;
return (uint32_t)(current_backlight);
}
static uint32_t dce_panel_cntl_hw_init(struct panel_cntl *panel_cntl)
{
struct dce_panel_cntl *dce_panel_cntl = TO_DCE_PANEL_CNTL(panel_cntl);
uint32_t value;
uint32_t current_backlight;
/* It must not be 0, so we have to restore them
* Bios bug w/a - period resets to zero,
* restoring to cache values which is always correct
*/
REG_GET(BL_PWM_CNTL, BL_ACTIVE_INT_FRAC_CNT, &value);
if (panel_cntl->stored_backlight_registers.BL_PWM_CNTL != 0) {
REG_WRITE(BL_PWM_CNTL,
panel_cntl->stored_backlight_registers.BL_PWM_CNTL);
REG_WRITE(BL_PWM_CNTL2,
panel_cntl->stored_backlight_registers.BL_PWM_CNTL2);
REG_WRITE(BL_PWM_PERIOD_CNTL,
panel_cntl->stored_backlight_registers.BL_PWM_PERIOD_CNTL);
REG_UPDATE(PWRSEQ_REF_DIV,
BL_PWM_REF_DIV,
panel_cntl->stored_backlight_registers.LVTMA_PWRSEQ_REF_DIV_BL_PWM_REF_DIV);
} else if ((value != 0) && (value != 1)) {
panel_cntl->stored_backlight_registers.BL_PWM_CNTL =
REG_READ(BL_PWM_CNTL);
panel_cntl->stored_backlight_registers.BL_PWM_CNTL2 =
REG_READ(BL_PWM_CNTL2);
Annotation
- Immediate include surface: `reg_helper.h`, `core_types.h`, `dc_dmub_srv.h`, `panel_cntl.h`, `dce_panel_cntl.h`, `atom.h`.
- Detected declarations: `function files`, `function dce_panel_cntl_hw_init`, `function dce_is_panel_backlight_on`, `function dce_is_panel_powered_on`, `function dce_store_backlight_level`, `function dce_driver_set_backlight`, `function dce_panel_cntl_destroy`, `function dce_panel_cntl_construct`.
- Atlas domain: Driver Families / drivers/gpu.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.