[PATCH v4 6/6] regmap: spmi: support base and extended register spaces
Josh Cartwright
joshc at codeaurora.org
Tue Jan 14 13:41:40 EST 2014
SPMI states that a slave may contain two register spaces, the Base
register space is a 5-bit byte-addressable space accessed via the
Register Read/Write and Register Zero Write command sequences, and the
Extended register space: a 16-bit byte-addressable space accessed via
the Extended Read/Write and Extended Read/Write Long command sequences.
Provide support for accessing both of these spaces, taking advantage of
the more bandwidth-efficient commands ('Register 0 Write' vs 'Register
Write', and 'Extended Register Read/Write' vs 'Extended Register
Read/Write Long') when possible.
Signed-off-by: Josh Cartwright <joshc at codeaurora.org>
---
drivers/base/regmap/regmap-spmi.c | 228 ++++++++++++++++++++++++++++++++------
include/linux/regmap.h | 12 +-
2 files changed, 205 insertions(+), 35 deletions(-)
diff --git a/drivers/base/regmap/regmap-spmi.c b/drivers/base/regmap/regmap-spmi.c
index ac23910..d7026dc 100644
--- a/drivers/base/regmap/regmap-spmi.c
+++ b/drivers/base/regmap/regmap-spmi.c
@@ -22,69 +22,235 @@
#include <linux/module.h>
#include <linux/init.h>
-static int regmap_spmi_read(void *context,
- const void *reg, size_t reg_size,
- void *val, size_t val_size)
+static int regmap_spmi_base_read(void *context,
+ const void *reg, size_t reg_size,
+ void *val, size_t val_size)
{
+ u8 addr = *(u8 *)reg;
+ int err = 0;
+
+ BUG_ON(reg_size != 1);
+
+ while (val_size-- && !err)
+ err = spmi_register_read(context, addr++, val++);
+
+ return err;
+}
+
+static int regmap_spmi_base_gather_write(void *context,
+ const void *reg, size_t reg_size,
+ const void *val, size_t val_size)
+{
+ const u8 *data = val;
+ u8 addr = *(u8 *)reg;
+ int err = 0;
+
+ BUG_ON(reg_size != 1);
+
+ /*
+ * SPMI defines a more bandwidth-efficient 'Register 0 Write' sequence,
+ * use it when possible.
+ */
+ if (addr == 0 && val_size) {
+ err = spmi_register_zero_write(context, *data);
+ if (err)
+ goto err_out;
+
+ data++;
+ addr++;
+ val_size--;
+ }
+
+ while (val_size) {
+ err = spmi_register_write(context, addr, *data);
+ if (err)
+ goto err_out;
+
+ data++;
+ addr++;
+ val_size--;
+ }
+
+err_out:
+ return err;
+}
+
+static int regmap_spmi_base_write(void *context, const void *data,
+ size_t count)
+{
+ BUG_ON(count < 1);
+ return regmap_spmi_base_gather_write(context, data, 1, data + 1,
+ count - 1);
+}
+
+static struct regmap_bus regmap_spmi_base = {
+ .read = regmap_spmi_base_read,
+ .write = regmap_spmi_base_write,
+ .gather_write = regmap_spmi_base_gather_write,
+ .reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
+ .val_format_endian_default = REGMAP_ENDIAN_NATIVE,
+};
+
+/**
+ * regmap_init_spmi_base(): Create regmap for the Base register space
+ * @sdev: SPMI 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.
+ */
+struct regmap *regmap_init_spmi_base(struct spmi_device *sdev,
+ const struct regmap_config *config)
+{
+ return regmap_init(&sdev->dev, ®map_spmi_base, sdev, config);
+}
+EXPORT_SYMBOL_GPL(regmap_init_spmi_base);
+
+/**
+ * devm_regmap_init_spmi_base(): Create managed regmap for Base register space
+ * @sdev: SPMI 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.
+ */
+struct regmap *devm_regmap_init_spmi_base(struct spmi_device *sdev,
+ const struct regmap_config *config)
+{
+ return devm_regmap_init(&sdev->dev, ®map_spmi_base, sdev, config);
+}
+EXPORT_SYMBOL_GPL(devm_regmap_init_spmi_base);
+
+static int regmap_spmi_ext_read(void *context,
+ const void *reg, size_t reg_size,
+ void *val, size_t val_size)
+{
+ int err = 0;
+ size_t len;
+ u16 addr;
+
BUG_ON(reg_size != 2);
- return spmi_ext_register_readl(context, *(u16 *)reg,
- val, val_size);
+
+ addr = *(u16 *)reg;
+
+ /*
+ * Split accesses into two to take advantage of the more
+ * bandwidth-efficient 'Extended Register Read' command when possible
+ */
+ while (addr <= 0xFF && val_size) {
+ len = min_t(size_t, val_size, 16);
+
+ err = spmi_ext_register_read(context, addr, val, len);
+ if (err)
+ goto err_out;
+
+ addr += len;
+ val += len;
+ val_size -= len;
+ }
+
+ while (val_size) {
+ len = min_t(size_t, val_size, 8);
+
+ err = spmi_ext_register_readl(context, addr, val, val_size);
+ if (err)
+ goto err_out;
+
+ addr += len;
+ val += len;
+ val_size -= len;
+ }
+
+err_out:
+ return err;
}
-static int regmap_spmi_gather_write(void *context,
- const void *reg, size_t reg_size,
- const void *val, size_t val_size)
+static int regmap_spmi_ext_gather_write(void *context,
+ const void *reg, size_t reg_size,
+ const void *val, size_t val_size)
{
+ int err = 0;
+ size_t len;
+ u16 addr;
+
BUG_ON(reg_size != 2);
- return spmi_ext_register_writel(context, *(u16 *)reg, val, val_size);
+
+ addr = *(u16 *)reg;
+
+ while (addr <= 0xFF && val_size) {
+ len = min_t(size_t, val_size, 16);
+
+ err = spmi_ext_register_write(context, addr, val, len);
+ if (err)
+ goto err_out;
+
+ addr += len;
+ val += len;
+ val_size -= len;
+ }
+
+ while (val_size) {
+ len = min_t(size_t, val_size, 8);
+
+ err = spmi_ext_register_writel(context, addr, val, len);
+ if (err)
+ goto err_out;
+
+ addr += len;
+ val += len;
+ val_size -= len;
+ }
+
+err_out:
+ return err;
}
-static int regmap_spmi_write(void *context, const void *data,
- size_t count)
+static int regmap_spmi_ext_write(void *context, const void *data,
+ size_t count)
{
BUG_ON(count < 2);
- return regmap_spmi_gather_write(context, data, 2, data + 2, count - 2);
+ return regmap_spmi_ext_gather_write(context, data, 2, data + 2,
+ count - 2);
}
-static struct regmap_bus regmap_spmi = {
- .read = regmap_spmi_read,
- .write = regmap_spmi_write,
- .gather_write = regmap_spmi_gather_write,
+static struct regmap_bus regmap_spmi_ext = {
+ .read = regmap_spmi_ext_read,
+ .write = regmap_spmi_ext_write,
+ .gather_write = regmap_spmi_ext_gather_write,
.reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
.val_format_endian_default = REGMAP_ENDIAN_NATIVE,
};
/**
- * regmap_init_spmi(): Initialize register map
- *
- * @sdev: Device that will be interacted with
- * @config: Configuration for register map
+ * regmap_init_spmi_ext(): Create regmap for Ext register space
+ * @sdev: 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.
*/
-struct regmap *regmap_init_spmi(struct spmi_device *sdev,
- const struct regmap_config *config)
+struct regmap *regmap_init_spmi_ext(struct spmi_device *sdev,
+ const struct regmap_config *config)
{
- return regmap_init(&sdev->dev, ®map_spmi, sdev, config);
+ return regmap_init(&sdev->dev, ®map_spmi_ext, sdev, config);
}
-EXPORT_SYMBOL_GPL(regmap_init_spmi);
+EXPORT_SYMBOL_GPL(regmap_init_spmi_ext);
/**
- * devm_regmap_init_spmi(): Initialise managed register map
- *
- * @sdev: Device that will be interacted with
- * @config: Configuration for register map
+ * devm_regmap_init_spmi_ext(): Create managed regmap for Ext register space
+ * @sdev: SPMI 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.
*/
-struct regmap *devm_regmap_init_spmi(struct spmi_device *sdev,
+struct regmap *devm_regmap_init_spmi_ext(struct spmi_device *sdev,
const struct regmap_config *config)
{
- return devm_regmap_init(&sdev->dev, ®map_spmi, sdev, config);
+ return devm_regmap_init(&sdev->dev, ®map_spmi_ext, sdev, config);
}
-EXPORT_SYMBOL_GPL(devm_regmap_init_spmi);
+EXPORT_SYMBOL_GPL(devm_regmap_init_spmi_ext);
MODULE_LICENSE("GPL");
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index e559078..847e7e6 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -321,8 +321,10 @@ struct regmap *regmap_init_i2c(struct i2c_client *i2c,
const struct regmap_config *config);
struct regmap *regmap_init_spi(struct spi_device *dev,
const struct regmap_config *config);
-struct regmap *regmap_init_spmi(struct spmi_device *dev,
- const struct regmap_config *config);
+struct regmap *regmap_init_spmi_base(struct spmi_device *dev,
+ const struct regmap_config *config);
+struct regmap *regmap_init_spmi_ext(struct spmi_device *dev,
+ const struct regmap_config *config);
struct regmap *regmap_init_mmio_clk(struct device *dev, const char *clk_id,
void __iomem *regs,
const struct regmap_config *config);
@@ -335,8 +337,10 @@ struct regmap *devm_regmap_init_i2c(struct i2c_client *i2c,
const struct regmap_config *config);
struct regmap *devm_regmap_init_spi(struct spi_device *dev,
const struct regmap_config *config);
-struct regmap *devm_regmap_init_spmi(struct spmi_device *dev,
- const struct regmap_config *config);
+struct regmap *devm_regmap_init_spmi_base(struct spmi_device *dev,
+ const struct regmap_config *config);
+struct regmap *devm_regmap_init_spmi_ext(struct spmi_device *dev,
+ const struct regmap_config *config);
struct regmap *devm_regmap_init_mmio_clk(struct device *dev, const char *clk_id,
void __iomem *regs,
const struct regmap_config *config);
--
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