[PATCH 1/2] regmap: Add DSI bus support

From: Jeffrey Hugo
Date: Wed Jul 03 2019 - 17:45:18 EST

Add basic support with a simple implementation that utilizes the generic
read/write commands to allow device registers to be configured.

Signed-off-by: Jeffrey Hugo <jeffrey.l.hugo@xxxxxxxxx>
---
drivers/base/regmap/Kconfig | 6 +++-
drivers/base/regmap/Makefile | 1 +
drivers/base/regmap/regmap-dsi.c | 62 ++++++++++++++++++++++++++++++++
include/linux/regmap.h | 37 +++++++++++++++++++
4 files changed, 105 insertions(+), 1 deletion(-)
create mode 100644 drivers/base/regmap/regmap-dsi.c

diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig
index c8bbf5322720..27669afa9d95 100644
--- a/drivers/base/regmap/Kconfig
+++ b/drivers/base/regmap/Kconfig
@@ -4,7 +4,7 @@
# subsystems should select the appropriate symbols.

config REGMAP
- default y if (REGMAP_I2C || REGMAP_SPI || REGMAP_SPMI || REGMAP_W1 || REGMAP_AC97 || REGMAP_MMIO || REGMAP_IRQ || REGMAP_I3C)
+ default y if (REGMAP_I2C || REGMAP_SPI || REGMAP_SPMI || REGMAP_W1 || REGMAP_AC97 || REGMAP_MMIO || REGMAP_IRQ || REGMAP_I3C || REGMAP_DSI)
select IRQ_DOMAIN if REGMAP_IRQ
bool

@@ -53,3 +53,7 @@ config REGMAP_SCCB
config REGMAP_I3C
tristate
depends on I3C
+
+config REGMAP_DSI
+ tristate
+ depends on DRM_MIPI_DSI
diff --git a/drivers/base/regmap/Makefile b/drivers/base/regmap/Makefile
index ff6c7d8ec1cd..c1cc81f3986f 100644
--- a/drivers/base/regmap/Makefile
+++ b/drivers/base/regmap/Makefile
@@ -17,3 +17,4 @@ obj-$(CONFIG_REGMAP_W1) += regmap-w1.o
obj-$(CONFIG_REGMAP_SOUNDWIRE) += regmap-sdw.o
obj-$(CONFIG_REGMAP_SCCB) += regmap-sccb.o
obj-$(CONFIG_REGMAP_I3C) += regmap-i3c.o
+obj-$(CONFIG_REGMAP_DSI) += regmap-dsi.o
diff --git a/drivers/base/regmap/regmap-dsi.c b/drivers/base/regmap/regmap-dsi.c
new file mode 100644
index 000000000000..0c2900e2fee0
--- /dev/null
+++ b/drivers/base/regmap/regmap-dsi.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Register map access API - DSI support
+//
+// Copyright (c) 2019 Jeffrey Hugo
+
+#include <drm/drm_mipi_dsi.h>
+#include <linux/regmap.h>
+#include <linux/module.h>
+
+#include "internal.h"
+
+static int dsi_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+ struct device *dev = context;
+ struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
+ char payload[2];
+ int ret;
+
+ payload[0] = (char)reg;
+ payload[1] = (char)val;
+
+ ret = mipi_dsi_generic_write(dsi, payload, 2);
+ return ret < 0 ? ret : 0;
+}
+
+static int dsi_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+ struct device *dev = context;
+ struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
+ int ret;
+
+ ret = mipi_dsi_generic_read(dsi, &reg, 1, val, 1);
+ return ret < 0 ? ret : 0;
+}
+
+static struct regmap_bus dsi_bus = {
+ .reg_write = dsi_reg_write,
+ .reg_read = dsi_reg_read,
+};
+
+struct regmap *__regmap_init_dsi(struct mipi_dsi_device *dsi,
+ const struct regmap_config *config,
+ struct lock_class_key *lock_key,
+ const char *lock_name)
+{
+ return __regmap_init(&dsi->dev, &dsi_bus, &dsi->dev, config,
+ lock_key, lock_name);
+}
+EXPORT_SYMBOL_GPL(__regmap_init_dsi);
+
+struct regmap *__devm_regmap_init_dsi(struct mipi_dsi_device *dsi,
+ const struct regmap_config *config,
+ struct lock_class_key *lock_key,
+ const char *lock_name)
+{
+ return __devm_regmap_init(&dsi->dev, &dsi_bus, &dsi->dev, config,
+ lock_key, lock_name);
+}
+EXPORT_SYMBOL_GPL(__devm_regmap_init_dsi);
+
+MODULE_LICENSE("GPL");
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index dfe493ac692d..858239f7859f 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -32,6 +32,7 @@ struct regmap_range_cfg;
struct regmap_field;
struct snd_ac97;
struct sdw_slave;
+struct mipi_dsi_device;

/* An enum of all the supported cache types */
enum regcache_type {
@@ -573,6 +574,10 @@ struct regmap *__regmap_init_sdw(struct sdw_slave *sdw,
const struct regmap_config *config,
struct lock_class_key *lock_key,
const char *lock_name);
+struct regmap *__regmap_init_dsi(struct mipi_dsi_device *dsi,
+ const struct regmap_config *config,
+ struct lock_class_key *lock_key,
+ const char *lock_name);

struct regmap *__devm_regmap_init(struct device *dev,
const struct regmap_bus *bus,
@@ -626,6 +631,10 @@ struct regmap *__devm_regmap_init_i3c(struct i3c_device *i3c,
const struct regmap_config *config,
struct lock_class_key *lock_key,
const char *lock_name);
+struct regmap *__devm_regmap_init_dsi(struct mipi_dsi_device *dsi,
+ const struct regmap_config *config,
+ struct lock_class_key *lock_key,
+ const char *lock_name);
/*
* Wrapper for regmap_init macros to include a unique lockdep key and name
* for each call. No-op if CONFIG_LOCKDEP is not set.
@@ -812,6 +821,19 @@ bool regmap_ac97_default_volatile(struct device *dev, unsigned int reg);
__regmap_lockdep_wrapper(__regmap_init_sdw, #config, \
sdw, config)

+/**
+ * regmap_init_dsi() - Initialise register map
+ *
+ * @dsi: Device that will be interacted with
+ * @config: Configuration for register map
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer to
+ * a struct regmap.
+ */
+#define regmap_init_dsi(dsi, config) \
+ __regmap_lockdep_wrapper(__regmap_init_dsi, #config, \
+ dsi, config)
+

/**
* devm_regmap_init() - Initialise managed register map
@@ -999,6 +1021,21 @@ bool regmap_ac97_default_volatile(struct device *dev, unsigned int reg);
__regmap_lockdep_wrapper(__devm_regmap_init_i3c, #config, \
i3c, config)

+/**
+ * devm_regmap_init_dsi() - Initialise managed register map
+ *
+ * @dsi: Device that will be interacted with
+ * @config: Configuration for register map
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer
+ * to a struct regmap. The regmap will be automatically freed by the
+ * device management code.
+ */
+#define devm_regmap_init_dsi(dsi, config) \
+ __regmap_lockdep_wrapper(__devm_regmap_init_dsi, #config, \
+ dsi, config)
+
+
int regmap_mmio_attach_clk(struct regmap *map, struct clk *clk);
void regmap_mmio_detach_clk(struct regmap *map);
void regmap_exit(struct regmap *map);
--
2.17.1