[v3,1/3] regmap: add i3c bus support

Commit Message

Vitor Soares July 10, 2019, 2:56 p.m. UTC

Add basic support for i3c bus.
This is a simple implementation that only give support
for SDR Read and Write commands.

Signed-off-by: Vitor Soares <[e-mail]>
---
 drivers/base/regmap/Kconfig      |  6 +++-
 drivers/base/regmap/Makefile     |  1 +
 drivers/base/regmap/regmap-i3c.c | 60 ++++++++++++++++++++++++++++++++++++++++
 include/linux/regmap.h           | 20 ++++++++++++++
 4 files changed, 86 insertions(+), 1 deletion(-)
 create mode 100644 drivers/base/regmap/regmap-i3c.c

Comments

Mark Brown July 10, 2019, 3:02 p.m. UTC | #1

On Wed, Jul 10, 2019 at 04:56:37PM +0200, Vitor Soares wrote:
> Add basic support for i3c bus.
> This is a simple implementation that only give support
> for SDR Read and Write commands.

Please do not submit new versions of already applied patches, please
submit incremental updates to the existing code.  Modifying existing
commits creates problems for other users building on top of those
commits so it's best practice to only change pubished git commits if
absolutely essential.

Patch

diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig
index 6ad5ef4..c8bbf53 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)
+	default y if (REGMAP_I2C || REGMAP_SPI || REGMAP_SPMI || REGMAP_W1 || REGMAP_AC97 || REGMAP_MMIO || REGMAP_IRQ || REGMAP_I3C)
 	select IRQ_DOMAIN if REGMAP_IRQ
 	bool
 
@@ -49,3 +49,7 @@  config REGMAP_SOUNDWIRE
 config REGMAP_SCCB
 	tristate
 	depends on I2C
+
+config REGMAP_I3C
+	tristate
+	depends on I3C
diff --git a/drivers/base/regmap/Makefile b/drivers/base/regmap/Makefile
index f5b4e88..ff6c7d8 100644
--- a/drivers/base/regmap/Makefile
+++ b/drivers/base/regmap/Makefile
@@ -16,3 +16,4 @@  obj-$(CONFIG_REGMAP_IRQ) += regmap-irq.o
 obj-$(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
diff --git a/drivers/base/regmap/regmap-i3c.c b/drivers/base/regmap/regmap-i3c.c
new file mode 100644
index 0000000..1578fb5
--- /dev/null
+++ b/drivers/base/regmap/regmap-i3c.c
@@ -0,0 +1,60 @@ 
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Synopsys, Inc. and/or its affiliates.
+
+#include <linux/regmap.h>
+#include <linux/i3c/device.h>
+#include <linux/i3c/master.h>
+#include <linux/module.h>
+
+static int regmap_i3c_write(void *context, const void *data, size_t count)
+{
+	struct device *dev = context;
+	struct i3c_device *i3c = dev_to_i3cdev(dev);
+	struct i3c_priv_xfer xfers[] = {
+		{
+			.rnw = false,
+			.len = count,
+			.data.out = data,
+		},
+	};
+
+	return i3c_device_do_priv_xfers(i3c, xfers, 1);
+}
+
+static int regmap_i3c_read(void *context,
+			   const void *reg, size_t reg_size,
+			   void *val, size_t val_size)
+{
+	struct device *dev = context;
+	struct i3c_device *i3c = dev_to_i3cdev(dev);
+	struct i3c_priv_xfer xfers[2];
+
+	xfers[0].rnw = false;
+	xfers[0].len = reg_size;
+	xfers[0].data.out = reg;
+
+	xfers[1].rnw = true;
+	xfers[1].len = val_size;
+	xfers[1].data.in = val;
+
+	return i3c_device_do_priv_xfers(i3c, xfers, 2);
+}
+
+static struct regmap_bus regmap_i3c = {
+	.write = regmap_i3c_write,
+	.read = regmap_i3c_read,
+};
+
+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)
+{
+	return __devm_regmap_init(&i3c->dev, &regmap_i3c, &i3c->dev, config,
+				  lock_key, lock_name);
+}
+EXPORT_SYMBOL_GPL(__devm_regmap_init_i3c);
+
+MODULE_AUTHOR("Vitor Soares <[e-mail]>");
+MODULE_DESCRIPTION("Regmap I3C Module");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index daeec7d..f65984d 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -25,6 +25,7 @@  struct module;
 struct clk;
 struct device;
 struct i2c_client;
+struct i3c_device;
 struct irq_domain;
 struct slim_device;
 struct spi_device;
@@ -624,6 +625,10 @@  struct regmap *__devm_regmap_init_slimbus(struct slim_device *slimbus,
 				 const struct regmap_config *config,
 				 struct lock_class_key *lock_key,
 				 const char *lock_name);
+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);
 /*
  * Wrapper for regmap_init macros to include a unique lockdep key and name
  * for each call. No-op if CONFIG_LOCKDEP is not set.
@@ -982,6 +987,21 @@  bool regmap_ac97_default_volatile(struct device *dev, unsigned int reg);
 #define devm_regmap_init_slimbus(slimbus, config)			\
 	__regmap_lockdep_wrapper(__devm_regmap_init_slimbus, #config,	\
 				slimbus, config)
+
+/**
+ * devm_regmap_init_i3c() - Initialise managed register map
+ *
+ * @i3c: 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_i3c(i3c, config)				\
+	__regmap_lockdep_wrapper(__devm_regmap_init_i3c, #config,	\
+				i3c, 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);