[RFC/RFT PATCH 1/4] drm/bridge: dw-hdmi: Switch to regmap for register access
From: Neil Armstrong
Date: Tue Jan 17 2017 - 07:32:44 EST
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 <narmstrong@xxxxxxxxxxxx>
---
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