The Synopsys Designware HDMI TX Controller does not enforce register access
on platforms instanciating it.
The current driver supports two different types of memory-mapped flat
register access, but in order to support the Amlogic Meson SoCs integration,
and provide a more generic way to handle all sorts of register mapping,
switch the register access to use the regmap infrastructure.

In the case of the registers are not flat memory-mapped or does not conform
at the actual driver implementation, a regmap struct can be given in the
plat_data and be used at probe or bind.

Since the AHB audio driver only uses direct memory access, using regmap only
allows the I2S audio driver to be registered.

Signed-off-by: Neil Armstrong <narmstr...@baylibre.com>
---
 drivers/gpu/drm/bridge/dw-hdmi.c | 105 +++++++++++++++++++++------------------
 include/drm/bridge/dw_hdmi.h     |   1 +
 2 files changed, 57 insertions(+), 49 deletions(-)

diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
index ca9d0ce..13747fe 100644
--- a/drivers/gpu/drm/bridge/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/dw-hdmi.c
@@ -20,6 +20,7 @@
 #include <linux/mutex.h>
 #include <linux/of_device.h>
 #include <linux/spinlock.h>
+#include <linux/regmap.h>
 
 #include <drm/drm_of.h>
 #include <drm/drmP.h>
@@ -167,8 +168,7 @@ struct dw_hdmi {
        unsigned int audio_n;
        bool audio_enable;
 
-       void (*write)(struct dw_hdmi *hdmi, u8 val, int offset);
-       u8 (*read)(struct dw_hdmi *hdmi, int offset);
+       struct regmap *regm;
 };
 
 #define HDMI_IH_PHY_STAT0_RX_SENSE \
@@ -179,42 +179,23 @@ struct dw_hdmi {
        (HDMI_PHY_RX_SENSE0 | HDMI_PHY_RX_SENSE1 | \
         HDMI_PHY_RX_SENSE2 | HDMI_PHY_RX_SENSE3)
 
-static void dw_hdmi_writel(struct dw_hdmi *hdmi, u8 val, int offset)
-{
-       writel(val, hdmi->regs + (offset << 2));
-}
-
-static u8 dw_hdmi_readl(struct dw_hdmi *hdmi, int offset)
-{
-       return readl(hdmi->regs + (offset << 2));
-}
-
-static void dw_hdmi_writeb(struct dw_hdmi *hdmi, u8 val, int offset)
-{
-       writeb(val, hdmi->regs + offset);
-}
-
-static u8 dw_hdmi_readb(struct dw_hdmi *hdmi, int offset)
-{
-       return readb(hdmi->regs + offset);
-}
-
 static inline void hdmi_writeb(struct dw_hdmi *hdmi, u8 val, int offset)
 {
-       hdmi->write(hdmi, val, offset);
+       regmap_write(hdmi->regm, offset, val);
 }
 
 static inline u8 hdmi_readb(struct dw_hdmi *hdmi, int offset)
 {
-       return hdmi->read(hdmi, offset);
+       unsigned int val = 0;
+
+       regmap_read(hdmi->regm, offset, &val);
+
+       return val;
 }
 
 static void hdmi_modb(struct dw_hdmi *hdmi, u8 data, u8 mask, unsigned reg)
 {
-       u8 val = hdmi_readb(hdmi, reg) & ~mask;
-
-       val |= data & mask;
-       hdmi_writeb(hdmi, val, reg);
+       regmap_update_bits(hdmi->regm, reg, mask, data);
 }
 
 static void hdmi_mask_writeb(struct dw_hdmi *hdmi, u8 data, unsigned int reg,
@@ -1949,6 +1930,21 @@ static int dw_hdmi_detect_phy(struct dw_hdmi *hdmi)
        return 0;
 }
 
+static struct regmap_config hdmi_regmap_8bit_config = {
+       .reg_bits       = 32,
+       .val_bits       = 8,
+       .reg_stride     = 1,
+       .max_register   = HDMI_I2CM_FS_SCL_LCNT_0_ADDR,
+};
+
+static struct regmap_config hdmi_regmap_32bit_config = {
+       .reg_bits       = 8,
+       .pad_bits       = 24,
+       .val_bits       = 32,
+       .reg_stride     = 4,
+       .max_register   = HDMI_I2CM_FS_SCL_LCNT_0_ADDR,
+};
+
 static struct dw_hdmi *
 __dw_hdmi_probe(struct platform_device *pdev,
                const struct dw_hdmi_plat_data *plat_data)
@@ -1958,7 +1954,8 @@ static int dw_hdmi_detect_phy(struct dw_hdmi *hdmi)
        struct platform_device_info pdevinfo;
        struct device_node *ddc_node;
        struct dw_hdmi *hdmi;
-       struct resource *iores;
+       struct regmap_config *reg_config = &hdmi_regmap_8bit_config;
+       struct resource *iores = NULL;
        int irq;
        int ret;
        u32 val = 1;
@@ -1982,20 +1979,21 @@ static int dw_hdmi_detect_phy(struct dw_hdmi *hdmi)
        mutex_init(&hdmi->audio_mutex);
        spin_lock_init(&hdmi->audio_lock);
 
-       of_property_read_u32(np, "reg-io-width", &val);
-
-       switch (val) {
-       case 4:
-               hdmi->write = dw_hdmi_writel;
-               hdmi->read = dw_hdmi_readl;
-               break;
-       case 1:
-               hdmi->write = dw_hdmi_writeb;
-               hdmi->read = dw_hdmi_readb;
-               break;
-       default:
-               dev_err(dev, "reg-io-width must be 1 or 4\n");
-               return ERR_PTR(-EINVAL);
+       if (plat_data->regm)
+               hdmi->regm = plat_data->regm;
+       else {
+               of_property_read_u32(np, "reg-io-width", &val);
+               switch (val) {
+               case 4:
+                       reg_config = &hdmi_regmap_32bit_config;
+                       break;
+               case 1:
+                       reg_config = &hdmi_regmap_8bit_config;
+                       break;
+               default:
+                       dev_err(dev, "reg-io-width must be 1 or 4\n");
+                       return ERR_PTR(-EINVAL);
+               }
        }
 
        ddc_node = of_parse_phandle(np, "ddc-i2c-bus", 0);
@@ -2011,11 +2009,20 @@ static int dw_hdmi_detect_phy(struct dw_hdmi *hdmi)
                dev_dbg(hdmi->dev, "no ddc property found\n");
        }
 
-       iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-       hdmi->regs = devm_ioremap_resource(dev, iores);
-       if (IS_ERR(hdmi->regs)) {
-               ret = PTR_ERR(hdmi->regs);
-               goto err_res;
+       if (!plat_data->regm) {
+               iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+               hdmi->regs = devm_ioremap_resource(dev, iores);
+               if (IS_ERR(hdmi->regs)) {
+                       ret = PTR_ERR(hdmi->regs);
+                       goto err_res;
+               }
+
+               hdmi->regm = devm_regmap_init_mmio(dev, hdmi->regs, reg_config);
+               if (IS_ERR(hdmi->regm)) {
+                       dev_err(dev, "Failed to configure regmap\n");
+                       ret = PTR_ERR(hdmi->regm);
+                       goto err_res;
+               }
        }
 
        hdmi->isfr_clk = devm_clk_get(hdmi->dev, "isfr");
@@ -2123,7 +2130,7 @@ static int dw_hdmi_detect_phy(struct dw_hdmi *hdmi)
        config0 = hdmi_readb(hdmi, HDMI_CONFIG0_ID);
        config3 = hdmi_readb(hdmi, HDMI_CONFIG3_ID);
 
-       if (config3 & HDMI_CONFIG3_AHBAUDDMA) {
+       if (iores && config3 & HDMI_CONFIG3_AHBAUDDMA) {
                struct dw_hdmi_audio_data audio;
 
                audio.phys = iores->start;
diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h
index 735a8ab..163842d 100644
--- a/include/drm/bridge/dw_hdmi.h
+++ b/include/drm/bridge/dw_hdmi.h
@@ -60,6 +60,7 @@ struct dw_hdmi_plat_data {
                             unsigned long mpixelclock);
        enum drm_mode_status (*mode_valid)(struct drm_connector *connector,
                                           struct drm_display_mode *mode);
+       struct regmap *regm;
 };
 
 int dw_hdmi_probe(struct platform_device *pdev,
-- 
1.9.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Reply via email to