regmap: Add 1-Wire bus support

Add basic support regmap (register map access) API for 1-Wire bus

Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig
index db9d00c36a3e941e466665de2535399e2ee4a076..413af5f940584891dd6a2dcea28f278e19ac4d41 100644 (file)
--- a/drivers/base/regmap/Kconfig
+++ b/drivers/base/regmap/Kconfig
@@ -3,7 +3,7 @@
 # subsystems should select the appropriate symbols.
 
 config REGMAP
-       default y if (REGMAP_I2C || REGMAP_SPI || REGMAP_SPMI || REGMAP_AC97 || REGMAP_MMIO || REGMAP_IRQ)
+       default y if (REGMAP_I2C || REGMAP_SPI || REGMAP_SPMI || REGMAP_W1 || REGMAP_AC97 || REGMAP_MMIO || REGMAP_IRQ)
        select LZO_COMPRESS
        select LZO_DECOMPRESS
        select IRQ_DOMAIN if REGMAP_IRQ
@@ -24,6 +24,10 @@ config REGMAP_SPMI
        tristate
        depends on SPMI
 
+config REGMAP_W1
+       tristate
+       depends on W1
+
 config REGMAP_MMIO
        tristate
 

diff --git a/drivers/base/regmap/Makefile b/drivers/base/regmap/Makefile
index 609e4c84f485b89ab0d219a3cfd06a2faf5a68ba..17741ae14ef4b85dcccd8850efee6ae290ff729b 100644 (file)
--- a/drivers/base/regmap/Makefile
+++ b/drivers/base/regmap/Makefile
@@ -10,3 +10,4 @@ obj-$(CONFIG_REGMAP_SPI) += regmap-spi.o
 obj-$(CONFIG_REGMAP_SPMI) += regmap-spmi.o
 obj-$(CONFIG_REGMAP_MMIO) += regmap-mmio.o
 obj-$(CONFIG_REGMAP_IRQ) += regmap-irq.o
+obj-$(CONFIG_REGMAP_W1) += regmap-w1.o

diff --git a/drivers/base/regmap/regmap-w1.c b/drivers/base/regmap/regmap-w1.c
new file mode 100644 (file)
index 0000000..5f04e7b
--- /dev/null
+++ b/drivers/base/regmap/regmap-w1.c
@@ -0,0 +1,245 @@
+/*
+ * Register map access API - W1 (1-Wire) support
+ *
+ * Copyright (C) 2017 OAO Radioavionica
+ * Author: Alex A. Mihaylov <minimumlaw@rambler.ru>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation
+ */
+
+#include <linux/regmap.h>
+#include <linux/module.h>
+#include "../../w1/w1.h"
+
+#include "internal.h"
+
+#define W1_CMD_READ_DATA       0x69
+#define W1_CMD_WRITE_DATA      0x6C
+
+/*
+ * 1-Wire slaves registers with addess 8 bit and data 8 bit
+ */
+
+static int w1_reg_a8_v8_read(void *context, unsigned int reg, unsigned int *val)
+{
+       struct device *dev = context;
+       struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+       int ret = 0;
+
+       if (reg > 255)
+               return -EINVAL;
+
+       mutex_lock(&sl->master->bus_mutex);
+       if (!w1_reset_select_slave(sl)) {
+               w1_write_8(sl->master, W1_CMD_READ_DATA);
+               w1_write_8(sl->master, reg);
+               *val = w1_read_8(sl->master);
+       } else {
+               ret = -ENODEV;
+       }
+       mutex_unlock(&sl->master->bus_mutex);
+
+       return ret;
+}
+
+static int w1_reg_a8_v8_write(void *context, unsigned int reg, unsigned int val)
+{
+       struct device *dev = context;
+       struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+       int ret = 0;
+
+       if (reg > 255)
+               return -EINVAL;
+
+       mutex_lock(&sl->master->bus_mutex);
+       if (!w1_reset_select_slave(sl)) {
+               w1_write_8(sl->master, W1_CMD_WRITE_DATA);
+               w1_write_8(sl->master, reg);
+               w1_write_8(sl->master, val);
+       } else {
+               ret = -ENODEV;
+       }
+       mutex_unlock(&sl->master->bus_mutex);
+
+       return ret;
+}
+
+/*
+ * 1-Wire slaves registers with addess 8 bit and data 16 bit
+ */
+
+static int w1_reg_a8_v16_read(void *context, unsigned int reg,
+                               unsigned int *val)
+{
+       struct device *dev = context;
+       struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+       int ret = 0;
+
+       if (reg > 255)
+               return -EINVAL;
+
+       mutex_lock(&sl->master->bus_mutex);
+       if (!w1_reset_select_slave(sl)) {
+               w1_write_8(sl->master, W1_CMD_READ_DATA);
+               w1_write_8(sl->master, reg);
+               *val = w1_read_8(sl->master);
+               *val |= w1_read_8(sl->master)<<8;
+       } else {
+               ret = -ENODEV;
+       }
+       mutex_unlock(&sl->master->bus_mutex);
+
+       return ret;
+}
+
+static int w1_reg_a8_v16_write(void *context, unsigned int reg,
+                               unsigned int val)
+{
+       struct device *dev = context;
+       struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+       int ret = 0;
+
+       if (reg > 255)
+               return -EINVAL;
+
+       mutex_lock(&sl->master->bus_mutex);
+       if (!w1_reset_select_slave(sl)) {
+               w1_write_8(sl->master, W1_CMD_WRITE_DATA);
+               w1_write_8(sl->master, reg);
+               w1_write_8(sl->master, val & 0x00FF);
+               w1_write_8(sl->master, val>>8 & 0x00FF);
+       } else {
+               ret = -ENODEV;
+       }
+       mutex_unlock(&sl->master->bus_mutex);
+
+       return ret;
+}
+
+/*
+ * 1-Wire slaves registers with addess 16 bit and data 16 bit
+ */
+
+static int w1_reg_a16_v16_read(void *context, unsigned int reg,
+                               unsigned int *val)
+{
+       struct device *dev = context;
+       struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+       int ret = 0;
+
+       if (reg > 65535)
+               return -EINVAL;
+
+       mutex_lock(&sl->master->bus_mutex);
+       if (!w1_reset_select_slave(sl)) {
+               w1_write_8(sl->master, W1_CMD_READ_DATA);
+               w1_write_8(sl->master, reg & 0x00FF);
+               w1_write_8(sl->master, reg>>8 & 0x00FF);
+               *val = w1_read_8(sl->master);
+               *val |= w1_read_8(sl->master)<<8;
+       } else {
+               ret = -ENODEV;
+       }
+       mutex_unlock(&sl->master->bus_mutex);
+
+       return ret;
+}
+
+static int w1_reg_a16_v16_write(void *context, unsigned int reg,
+                               unsigned int val)
+{
+       struct device *dev = context;
+       struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+       int ret = 0;
+
+       if (reg > 65535)
+               return -EINVAL;
+
+       mutex_lock(&sl->master->bus_mutex);
+       if (!w1_reset_select_slave(sl)) {
+               w1_write_8(sl->master, W1_CMD_WRITE_DATA);
+               w1_write_8(sl->master, reg & 0x00FF);
+               w1_write_8(sl->master, reg>>8 & 0x00FF);
+               w1_write_8(sl->master, val & 0x00FF);
+               w1_write_8(sl->master, val>>8 & 0x00FF);
+       } else {
+               ret = -ENODEV;
+       }
+       mutex_unlock(&sl->master->bus_mutex);
+
+       return ret;
+}
+
+/*
+ * Various types of supported bus addressing
+ */
+
+static struct regmap_bus regmap_w1_bus_a8_v8 = {
+       .reg_read = w1_reg_a8_v8_read,
+       .reg_write = w1_reg_a8_v8_write,
+};
+
+static struct regmap_bus regmap_w1_bus_a8_v16 = {
+       .reg_read = w1_reg_a8_v16_read,
+       .reg_write = w1_reg_a8_v16_write,
+};
+
+static struct regmap_bus regmap_w1_bus_a16_v16 = {
+       .reg_read = w1_reg_a16_v16_read,
+       .reg_write = w1_reg_a16_v16_write,
+};
+
+static const struct regmap_bus *regmap_get_w1_bus(struct device *w1_dev,
+                                       const struct regmap_config *config)
+{
+       if (config->reg_bits == 8 && config->val_bits == 8)
+               return &regmap_w1_bus_a8_v8;
+
+       if (config->reg_bits == 8 && config->val_bits == 16)
+               return &regmap_w1_bus_a8_v16;
+
+       if (config->reg_bits == 16 && config->val_bits == 16)
+               return &regmap_w1_bus_a16_v16;
+
+       return ERR_PTR(-ENOTSUPP);
+}
+
+struct regmap *__regmap_init_w1(struct device *w1_dev,
+                                const struct regmap_config *config,
+                                struct lock_class_key *lock_key,
+                                const char *lock_name)
+{
+
+       const struct regmap_bus *bus = regmap_get_w1_bus(w1_dev, config);
+
+       if (IS_ERR(bus))
+               return ERR_CAST(bus);
+
+       return __regmap_init(w1_dev, bus, w1_dev, config,
+                        lock_key, lock_name);
+
+       return NULL;
+}
+EXPORT_SYMBOL_GPL(__regmap_init_w1);
+
+struct regmap *__devm_regmap_init_w1(struct device *w1_dev,
+                                const struct regmap_config *config,
+                                struct lock_class_key *lock_key,
+                                const char *lock_name)
+{
+
+       const struct regmap_bus *bus = regmap_get_w1_bus(w1_dev, config);
+
+       if (IS_ERR(bus))
+               return ERR_CAST(bus);
+
+       return __devm_regmap_init(w1_dev, bus, w1_dev, config,
+                                lock_key, lock_name);
+
+       return NULL;
+}
+EXPORT_SYMBOL_GPL(__devm_regmap_init_w1);
+
+MODULE_LICENSE("GPL");

diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index e88649225a6073fea86bc77d99bdf3109fe7838d..86eeacc1425af1e61bf3546d939c1cec5e2fc355 100644 (file)
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -461,6 +461,10 @@ struct regmap *__regmap_init_spmi_ext(struct spmi_device *dev,
                                      const struct regmap_config *config,
                                      struct lock_class_key *lock_key,
                                      const char *lock_name);
+struct regmap *__regmap_init_w1(struct device *w1_dev,
+                                const struct regmap_config *config,
+                                struct lock_class_key *lock_key,
+                                const char *lock_name);
 struct regmap *__regmap_init_mmio_clk(struct device *dev, const char *clk_id,
                                      void __iomem *regs,
                                      const struct regmap_config *config,
@@ -493,6 +497,10 @@ struct regmap *__devm_regmap_init_spmi_ext(struct spmi_device *dev,
                                           const struct regmap_config *config,
                                           struct lock_class_key *lock_key,
                                           const char *lock_name);
+struct regmap *__devm_regmap_init_w1(struct device *w1_dev,
+                                     const struct regmap_config *config,
+                                     struct lock_class_key *lock_key,
+                                     const char *lock_name);
 struct regmap *__devm_regmap_init_mmio_clk(struct device *dev,
                                           const char *clk_id,
                                           void __iomem *regs,
@@ -596,6 +604,19 @@ int regmap_attach_dev(struct device *dev, struct regmap *map,
        __regmap_lockdep_wrapper(__regmap_init_spmi_ext, #config,       \
                                dev, config)
 
+/**
+ * regmap_init_w1() - Initialise register map
+ *
+ * @w1_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_w1(w1_dev, config)                                 \
+       __regmap_lockdep_wrapper(__regmap_init_w1, #config,             \
+                               w1_dev, config)
+
 /**
  * regmap_init_mmio_clk() - Initialise register map with register clock
  *
@@ -711,6 +732,19 @@ bool regmap_ac97_default_volatile(struct device *dev, unsigned int reg);
        __regmap_lockdep_wrapper(__devm_regmap_init_spmi_ext, #config,  \
                                dev, config)
 
+/**
+ * devm_regmap_init_w1() - Initialise managed register map
+ *
+ * @w1_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_w1(w1_dev, config)                            \
+       __regmap_lockdep_wrapper(__devm_regmap_init_w1, #config,        \
+                               w1_dev, config)
 /**
  * devm_regmap_init_mmio_clk() - Initialise managed register map with clock
  *