regmap: Add FSI bus support

Add regmap support for the FSI bus.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20221102205148.1334459-2-eajames@linux.ibm.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig
index 159bac6..cd4bb64 100644 (file)
--- 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 11facb3..6990de7 100644 (file)
--- 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 (file)
index 0000000..3d2f3cb
--- /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 ca3434d..e477112 100644 (file)
--- 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.
@@ -920,6 +930,19 @@ bool regmap_ac97_default_volatile(struct device *dev, unsigned int reg);
                                 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
  *
  * @dev: Device that will be interacted with
@@ -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);