drm/sun4i: hdmi: Add support for controller hardware variants

The HDMI controller found in earlier Allwinner SoCs have slight
differences between the A10, A10s, and the A31:

  - Need different initial values for the PLL related registers

  - Different behavior of the DDC and TMDS clocks

  - Different register layout for the DDC portion

  - Separate DDC parent clock on the A31

  - Explicit reset control

For the A31, the HDMI TMDS clock has a different value offset for
the divider. The HDMI DDC block is different from the one in the
other SoCs. As far as the DDC clock goes, it has no pre-divider,
as it is clocked from a slower parent clock, not the TMDS clock.
The divider offset from the register value is different. And the
clock control register is at a different offset.

A new variant data structure is created to store pointers to the
above functions, structures, and the different initial values.
Another flag notates whether there is a separate DDC parent clock.
If not, the TMDS clock is passed to the DDC clock create function,
as before.

Regmap fields are used to deal with the different register layout
of the DDC block.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010032008.682-8-wens@csie.org

1 files changed, 72 insertions, 0 deletions

diff --git a/drivers/gpu/drm/sun4i/sun4i_hdmi.h b/drivers/gpu/drm/sun4i/sun4i_hdmi.h
index aef157d..3057e31 100644
--- a/drivers/gpu/drm/sun4i/sun4i_hdmi.h
+++ b/drivers/gpu/drm/sun4i/sun4i_hdmi.h
@@ -14,6 +14,7 @@
 
 #include <drm/drm_connector.h>
 #include <drm/drm_encoder.h>
+#include <linux/regmap.h>
 
 #include <media/cec-pin.h>
 
@@ -157,6 +158,55 @@ enum sun4i_hdmi_pkt_type {
 	SUN4I_HDMI_PKT_END = 15,
 };
 
+struct sun4i_hdmi_variant {
+	bool has_ddc_parent_clk;
+	bool has_reset_control;
+
+	u32 pad_ctrl0_init_val;
+	u32 pad_ctrl1_init_val;
+	u32 pll_ctrl_init_val;
+
+	struct reg_field ddc_clk_reg;
+	u8 ddc_clk_pre_divider;
+	u8 ddc_clk_m_offset;
+
+	u8 tmds_clk_div_offset;
+
+	/* Register fields for I2C adapter */
+	struct reg_field	field_ddc_en;
+	struct reg_field	field_ddc_start;
+	struct reg_field	field_ddc_reset;
+	struct reg_field	field_ddc_addr_reg;
+	struct reg_field	field_ddc_slave_addr;
+	struct reg_field	field_ddc_int_mask;
+	struct reg_field	field_ddc_int_status;
+	struct reg_field	field_ddc_fifo_clear;
+	struct reg_field	field_ddc_fifo_rx_thres;
+	struct reg_field	field_ddc_fifo_tx_thres;
+	struct reg_field	field_ddc_byte_count;
+	struct reg_field	field_ddc_cmd;
+	struct reg_field	field_ddc_sda_en;
+	struct reg_field	field_ddc_sck_en;
+
+	/* DDC FIFO register offset */
+	u32			ddc_fifo_reg;
+
+	/*
+	 * DDC FIFO threshold boundary conditions
+	 *
+	 * This is used to cope with the threshold boundary condition
+	 * being slightly different on sun5i and sun6i.
+	 *
+	 * On sun5i the threshold is exclusive, i.e. does not include,
+	 * the value of the threshold. ( > for RX; < for TX )
+	 * On sun6i the threshold is inclusive, i.e. includes, the
+	 * value of the threshold. ( >= for RX; <= for TX )
+	 */
+	bool			ddc_fifo_thres_incl;
+
+	bool			ddc_fifo_has_dir;
+};
+
 struct sun4i_hdmi {
 	struct drm_connector	connector;
 	struct drm_encoder	encoder;
@@ -165,9 +215,13 @@ struct sun4i_hdmi {
 	void __iomem		*base;
 	struct regmap		*regmap;
 
+	/* Reset control */
+	struct reset_control	*reset;
+
 	/* Parent clocks */
 	struct clk		*bus_clk;
 	struct clk		*mod_clk;
+	struct clk		*ddc_parent_clk;
 	struct clk		*pll0_clk;
 	struct clk		*pll1_clk;
 
@@ -177,10 +231,28 @@ struct sun4i_hdmi {
 
 	struct i2c_adapter	*i2c;
 
+	/* Regmap fields for I2C adapter */
+	struct regmap_field	*field_ddc_en;
+	struct regmap_field	*field_ddc_start;
+	struct regmap_field	*field_ddc_reset;
+	struct regmap_field	*field_ddc_addr_reg;
+	struct regmap_field	*field_ddc_slave_addr;
+	struct regmap_field	*field_ddc_int_mask;
+	struct regmap_field	*field_ddc_int_status;
+	struct regmap_field	*field_ddc_fifo_clear;
+	struct regmap_field	*field_ddc_fifo_rx_thres;
+	struct regmap_field	*field_ddc_fifo_tx_thres;
+	struct regmap_field	*field_ddc_byte_count;
+	struct regmap_field	*field_ddc_cmd;
+	struct regmap_field	*field_ddc_sda_en;
+	struct regmap_field	*field_ddc_sck_en;
+
 	struct sun4i_drv	*drv;
 
 	bool			hdmi_monitor;
 	struct cec_adapter	*cec_adap;
+
+	const struct sun4i_hdmi_variant	*variant;
 };
 
 int sun4i_ddc_create(struct sun4i_hdmi *hdmi, struct clk *clk);