[v2,1/5] regmap: Add FSI bus support

Message ID 20221102205148.1334459-2-eajames@linux.ibm.com
State New
Headers
Series fsi: Add regmap and refactor sbefifo |

Commit Message

Eddie James Nov. 2, 2022, 8:51 p.m. UTC
  Add regmap support for the FSI bus.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 drivers/base/regmap/Kconfig      |   6 +-
 drivers/base/regmap/Makefile     |   1 +
 drivers/base/regmap/regmap-fsi.c | 231 +++++++++++++++++++++++++++++++
 include/linux/regmap.h           |  37 +++++
 4 files changed, 274 insertions(+), 1 deletion(-)
 create mode 100644 drivers/base/regmap/regmap-fsi.c
  

Comments

Mark Brown Nov. 3, 2022, 2:54 p.m. UTC | #1
On Wed, Nov 02, 2022 at 03:51:44PM -0500, Eddie James wrote:
> Add regmap support for the FSI bus.
> 
> Signed-off-by: Eddie James <eajames@linux.ibm.com>
> ---
>  drivers/base/regmap/Kconfig      |   6 +-
>  drivers/base/regmap/Makefile     |   1 +
>  drivers/base/regmap/regmap-fsi.c | 231 +++++++++++++++++++++++++++++++
>  include/linux/regmap.h           |  37 +++++

I thought the plan was to put this in the MFD since that's the only
user?
  
Eddie James Nov. 3, 2022, 2:59 p.m. UTC | #2
On 11/3/22 09:54, Mark Brown wrote:
> On Wed, Nov 02, 2022 at 03:51:44PM -0500, Eddie James wrote:
>> Add regmap support for the FSI bus.
>>
>> Signed-off-by: Eddie James <eajames@linux.ibm.com>
>> ---
>>   drivers/base/regmap/Kconfig      |   6 +-
>>   drivers/base/regmap/Makefile     |   1 +
>>   drivers/base/regmap/regmap-fsi.c | 231 +++++++++++++++++++++++++++++++
>>   include/linux/regmap.h           |  37 +++++
> I thought the plan was to put this in the MFD since that's the only
> user?


For the I2C responder regmap, yes, that's what I've done. The FSI regmap 
could be used anywhere in the future. We could switch a number of 
drivers to use the FSI regmap if desired, so I feel it's worth it to put 
it in the regmap properly.


Thanks,

Eddie
  

Patch

diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig
index 159bac6c5046..cd4bb642b9de 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_SOUNDWIRE || REGMAP_SOUNDWIRE_MBQ || REGMAP_SCCB || REGMAP_I3C || REGMAP_SPI_AVMM || REGMAP_MDIO)
+	default y if (REGMAP_I2C || REGMAP_SPI || REGMAP_SPMI || REGMAP_W1 || REGMAP_AC97 || REGMAP_MMIO || REGMAP_IRQ || REGMAP_SOUNDWIRE || REGMAP_SOUNDWIRE_MBQ || REGMAP_SCCB || REGMAP_I3C || REGMAP_SPI_AVMM || REGMAP_MDIO || REGMAP_FSI)
 	select IRQ_DOMAIN if REGMAP_IRQ
 	select MDIO_BUS if REGMAP_MDIO
 	bool
@@ -65,3 +65,7 @@  config REGMAP_I3C
 config REGMAP_SPI_AVMM
 	tristate
 	depends on SPI
+
+config REGMAP_FSI
+	tristate
+	depends on FSI
diff --git a/drivers/base/regmap/Makefile b/drivers/base/regmap/Makefile
index 11facb32a027..6990de7ca9a9 100644
--- a/drivers/base/regmap/Makefile
+++ b/drivers/base/regmap/Makefile
@@ -20,3 +20,4 @@  obj-$(CONFIG_REGMAP_SCCB) += regmap-sccb.o
 obj-$(CONFIG_REGMAP_I3C) += regmap-i3c.o
 obj-$(CONFIG_REGMAP_SPI_AVMM) += regmap-spi-avmm.o
 obj-$(CONFIG_REGMAP_MDIO) += regmap-mdio.o
+obj-$(CONFIG_REGMAP_FSI) += regmap-fsi.o
diff --git a/drivers/base/regmap/regmap-fsi.c b/drivers/base/regmap/regmap-fsi.c
new file mode 100644
index 000000000000..3d2f3cb31d5e
--- /dev/null
+++ b/drivers/base/regmap/regmap-fsi.c
@@ -0,0 +1,231 @@ 
+// SPDX-License-Identifier: GPL-2.0
+//
+// Register map access API - FSI support
+//
+// Copyright 2022 IBM Corp
+//
+// Author: Eddie James <eajames@linux.ibm.com>
+
+#include <linux/fsi.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include "internal.h"
+
+static int regmap_fsi32_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+	u32 v;
+	int ret;
+
+	ret = fsi_slave_read(context, reg, &v, sizeof(v));
+	if (ret)
+		return ret;
+
+	*val = v;
+	return 0;
+}
+
+static int regmap_fsi32_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+	u32 v = val;
+
+	return fsi_slave_write(context, reg, &v, sizeof(v));
+}
+
+static const struct regmap_bus regmap_fsi32 = {
+	.reg_write = regmap_fsi32_reg_write,
+	.reg_read = regmap_fsi32_reg_read,
+};
+
+static int regmap_fsi32le_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+	__be32 v;
+	int ret;
+
+	ret = fsi_slave_read(context, reg, &v, sizeof(v));
+	if (ret)
+		return ret;
+
+	*val = be32_to_cpu(v);
+	return 0;
+}
+
+static int regmap_fsi32le_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+	__be32 v = cpu_to_be32(val);
+
+	return fsi_slave_write(context, reg, &v, sizeof(v));
+}
+
+static const struct regmap_bus regmap_fsi32le = {
+	.reg_write = regmap_fsi32le_reg_write,
+	.reg_read = regmap_fsi32le_reg_read,
+};
+
+static int regmap_fsi16_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+	u16 v;
+	int ret;
+
+	ret = fsi_slave_read(context, reg, &v, sizeof(v));
+	if (ret)
+		return ret;
+
+	*val = v;
+	return 0;
+}
+
+static int regmap_fsi16_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+	u16 v;
+
+	if (val > 0xffff)
+		return -EINVAL;
+
+	v = val;
+	return fsi_slave_write(context, reg, &v, sizeof(v));
+}
+
+static const struct regmap_bus regmap_fsi16 = {
+	.reg_write = regmap_fsi16_reg_write,
+	.reg_read = regmap_fsi16_reg_read,
+};
+
+static int regmap_fsi16le_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+	__be16 v;
+	int ret;
+
+	ret = fsi_slave_read(context, reg, &v, sizeof(v));
+	if (ret)
+		return ret;
+
+	*val = be16_to_cpu(v);
+	return 0;
+}
+
+static int regmap_fsi16le_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+	__be16 v;
+
+	if (val > 0xffff)
+		return -EINVAL;
+
+	v = cpu_to_be16(val);
+	return fsi_slave_write(context, reg, &v, sizeof(v));
+}
+
+static const struct regmap_bus regmap_fsi16le = {
+	.reg_write = regmap_fsi16le_reg_write,
+	.reg_read = regmap_fsi16le_reg_read,
+};
+
+static int regmap_fsi8_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+	u8 v;
+	int ret;
+
+	ret = fsi_slave_read(context, reg, &v, sizeof(v));
+	if (ret)
+		return ret;
+
+	*val = v;
+	return 0;
+}
+
+static int regmap_fsi8_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+	u8 v;
+
+	if (val > 0xff)
+		return -EINVAL;
+
+	v = val;
+	return fsi_slave_write(context, reg, &v, sizeof(v));
+}
+
+static const struct regmap_bus regmap_fsi8 = {
+	.reg_write = regmap_fsi8_reg_write,
+	.reg_read = regmap_fsi8_reg_read,
+};
+
+static const struct regmap_bus *regmap_get_fsi_bus(struct fsi_device *fsi_dev,
+						   const struct regmap_config *config)
+{
+	const struct regmap_bus *bus = NULL;
+
+	if (config->reg_bits == 8 || config->reg_bits == 16 || config->reg_bits == 32) {
+		switch (config->val_bits) {
+		case 8:
+			bus = &regmap_fsi8;
+			break;
+		case 16:
+			switch (regmap_get_val_endian(&fsi_dev->dev, NULL, config)) {
+			case REGMAP_ENDIAN_LITTLE:
+#ifdef __LITTLE_ENDIAN
+			case REGMAP_ENDIAN_NATIVE:
+#endif
+				bus = &regmap_fsi16le;
+				break;
+			case REGMAP_ENDIAN_DEFAULT:
+			case REGMAP_ENDIAN_BIG:
+#ifdef __BIG_ENDIAN
+			case REGMAP_ENDIAN_NATIVE:
+#endif
+				bus = &regmap_fsi16;
+				break;
+			default:
+				break;
+			}
+			break;
+		case 32:
+			switch (regmap_get_val_endian(&fsi_dev->dev, NULL, config)) {
+			case REGMAP_ENDIAN_LITTLE:
+#ifdef __LITTLE_ENDIAN
+			case REGMAP_ENDIAN_NATIVE:
+#endif
+				bus = &regmap_fsi32le;
+				break;
+			case REGMAP_ENDIAN_DEFAULT:
+			case REGMAP_ENDIAN_BIG:
+#ifdef __BIG_ENDIAN
+			case REGMAP_ENDIAN_NATIVE:
+#endif
+				bus = &regmap_fsi32;
+				break;
+			default:
+				break;
+			}
+			break;
+		}
+	}
+
+	return bus ?: ERR_PTR(-EOPNOTSUPP);
+}
+
+struct regmap *__regmap_init_fsi(struct fsi_device *fsi_dev, const struct regmap_config *config,
+				 struct lock_class_key *lock_key, const char *lock_name)
+{
+	const struct regmap_bus *bus = regmap_get_fsi_bus(fsi_dev, config);
+
+	if (IS_ERR(bus))
+		return ERR_CAST(bus);
+
+	return __regmap_init(&fsi_dev->dev, bus, fsi_dev->slave, config, lock_key, lock_name);
+}
+EXPORT_SYMBOL_GPL(__regmap_init_fsi);
+
+struct regmap *__devm_regmap_init_fsi(struct fsi_device *fsi_dev,
+				      const struct regmap_config *config,
+				      struct lock_class_key *lock_key, const char *lock_name)
+{
+	const struct regmap_bus *bus = regmap_get_fsi_bus(fsi_dev, config);
+
+	if (IS_ERR(bus))
+		return ERR_CAST(bus);
+
+	return __devm_regmap_init(&fsi_dev->dev, bus, fsi_dev->slave, config, lock_key, lock_name);
+}
+EXPORT_SYMBOL_GPL(__devm_regmap_init_fsi);
+
+MODULE_LICENSE("GPL");
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index ca3434dca3a0..e477112fb1c7 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -24,6 +24,7 @@  struct module;
 struct clk;
 struct device;
 struct device_node;
+struct fsi_device;
 struct i2c_client;
 struct i3c_device;
 struct irq_domain;
@@ -628,6 +629,10 @@  struct regmap *__regmap_init_spi_avmm(struct spi_device *spi,
 				      const struct regmap_config *config,
 				      struct lock_class_key *lock_key,
 				      const char *lock_name);
+struct regmap *__regmap_init_fsi(struct fsi_device *fsi_dev,
+				 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,
@@ -693,6 +698,11 @@  struct regmap *__devm_regmap_init_spi_avmm(struct spi_device *spi,
 					   const struct regmap_config *config,
 					   struct lock_class_key *lock_key,
 					   const char *lock_name);
+struct regmap *__devm_regmap_init_fsi(struct fsi_device *fsi_dev,
+				      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.
@@ -919,6 +929,19 @@  bool regmap_ac97_default_volatile(struct device *dev, unsigned int reg);
 	__regmap_lockdep_wrapper(__regmap_init_spi_avmm, #config,		\
 				 spi, config)
 
+/**
+ * regmap_init_fsi() - Initialise register map
+ *
+ * @fsi_dev: 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_fsi(fsi_dev, config)				\
+	__regmap_lockdep_wrapper(__regmap_init_fsi, #config, fsi_dev,	\
+				 config)
+
 /**
  * devm_regmap_init() - Initialise managed register map
  *
@@ -1148,6 +1171,20 @@  bool regmap_ac97_default_volatile(struct device *dev, unsigned int reg);
 	__regmap_lockdep_wrapper(__devm_regmap_init_spi_avmm, #config,	\
 				 spi, config)
 
+/**
+ * devm_regmap_init_fsi() - Initialise managed register map
+ *
+ * @fsi_dev: 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_fsi(fsi_dev, config)				\
+	__regmap_lockdep_wrapper(__devm_regmap_init_fsi, #config,	\
+				 fsi_dev, 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);