mfd mc13892: Add spi support

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

2 files changed, 111 insertions, 10 deletions

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 7c27418bf1..96440d852f 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1,7 +1,7 @@
 menu MFD
 
 config I2C_MC13892
-	depends on I2C
+	depends on I2C || SPI
 	bool "MC13892 a.k.a. PMIC driver"
 
 config I2C_MC34704
diff --git a/drivers/mfd/mc13892.c b/drivers/mfd/mc13892.c
index 240a7a9e79..2f415fcbbd 100644
--- a/drivers/mfd/mc13892.c
+++ b/drivers/mfd/mc13892.c
@@ -24,6 +24,7 @@
 #include <driver.h>
 #include <xfuncs.h>
 #include <errno.h>
+#include <spi/spi.h>
 
 #include <i2c/i2c.h>
 #include <mfd/mc13892.h>
@@ -43,7 +44,56 @@ struct mc13892 *mc13892_get(void)
 }
 EXPORT_SYMBOL(mc13892_get);
 
-int mc13892_reg_read(struct mc13892 *mc13892, enum mc13892_reg reg, u32 *val)
+#ifdef CONFIG_SPI
+static int spi_rw(struct spi_device *spi, void * buf, size_t len)
+{
+	int ret;
+
+	struct spi_transfer t = {
+		.tx_buf = (const void *)buf,
+		.rx_buf = buf,
+		.len = len,
+		.cs_change = 0,
+		.delay_usecs = 0,
+	};
+	struct spi_message m;
+
+	spi_message_init(&m);
+	spi_message_add_tail(&t, &m);
+
+	if ((ret = spi_sync(spi, &m)))
+		return ret;
+	return 0;
+}
+
+#define MXC_PMIC_REG_NUM(reg)	(((reg) & 0x3f) << 25)
+#define MXC_PMIC_WRITE		(1 << 31)
+
+static int mc13892_spi_reg_read(struct mc13892 *mc13892, enum mc13892_reg reg, u32 *val)
+{
+	uint32_t buf;
+
+	buf = MXC_PMIC_REG_NUM(reg);
+
+	spi_rw(mc13892->spi, &buf, 4);
+
+	*val = buf;
+
+	return 0;
+}
+
+static int mc13892_spi_reg_write(struct mc13892 *mc13892, enum mc13892_reg reg, u32 val)
+{
+	uint32_t buf = MXC_PMIC_REG_NUM(reg) | MXC_PMIC_WRITE | (val & 0xffffff);
+
+	spi_rw(mc13892->spi, &buf, 4);
+
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_I2C
+static int mc13892_i2c_reg_read(struct mc13892 *mc13892, enum mc13892_reg reg, u32 *val)
 {
 	u8 buf[3];
 	int ret;
@@ -53,9 +103,8 @@ int mc13892_reg_read(struct mc13892 *mc13892, enum mc13892_reg reg, u32 *val)
 
 	return ret == 3 ? 0 : ret;
 }
-EXPORT_SYMBOL(mc13892_reg_read)
 
-int mc13892_reg_write(struct mc13892 *mc13892, enum mc13892_reg reg, u32 val)
+static int mc13892_i2c_reg_write(struct mc13892 *mc13892, enum mc13892_reg reg, u32 val)
 {
 	u8 buf[] = {
 		val >> 16,
@@ -68,8 +117,36 @@ int mc13892_reg_write(struct mc13892 *mc13892, enum mc13892_reg reg, u32 val)
 
 	return ret == 3 ? 0 : ret;
 }
+#endif
+
+int mc13892_reg_write(struct mc13892 *mc13892, enum mc13892_reg reg, u32 val)
+{
+#ifdef CONFIG_I2C
+	if (mc13892->mode == MC13892_MODE_I2C)
+		return mc13892_i2c_reg_write(mc13892, reg, val);
+#endif
+#ifdef CONFIG_SPI
+	if (mc13892->mode == MC13892_MODE_SPI)
+		return mc13892_spi_reg_write(mc13892, reg, val);
+#endif
+	return -EINVAL;
+}
 EXPORT_SYMBOL(mc13892_reg_write)
 
+int mc13892_reg_read(struct mc13892 *mc13892, enum mc13892_reg reg, u32 *val)
+{
+#ifdef CONFIG_I2C
+	if (mc13892->mode == MC13892_MODE_I2C)
+		return mc13892_i2c_reg_read(mc13892, reg, val);
+#endif
+#ifdef CONFIG_SPI
+	if (mc13892->mode == MC13892_MODE_SPI)
+		return mc13892_spi_reg_read(mc13892, reg, val);
+#endif
+	return -EINVAL;
+}
+EXPORT_SYMBOL(mc13892_reg_read)
+
 int mc13892_set_bits(struct mc13892 *mc13892, enum mc13892_reg reg, u32 mask, u32 val)
 {
 	u32 tmp;
@@ -133,14 +210,22 @@ static struct file_operations mc_fops = {
 	.write	= mc_write,
 };
 
-static int mc_probe(struct device_d *dev)
+static int mc_probe(struct device_d *dev, enum mc13892_mode mode)
 {
 	if (mc_dev)
 		return -EBUSY;
 
 	mc_dev = xzalloc(sizeof(struct mc13892));
+	mc_dev->mode = mode;
 	mc_dev->cdev.name = DRIVERNAME;
-	mc_dev->client = to_i2c_client(dev);
+	if (mode == MC13892_MODE_I2C) {
+		mc_dev->client = to_i2c_client(dev);
+	}
+	if (mode == MC13892_MODE_SPI) {
+		mc_dev->spi = dev->type_data;
+		mc_dev->spi->mode = SPI_MODE_0 | SPI_CS_HIGH;
+		mc_dev->spi->bits_per_word = 32;
+	}
 	mc_dev->cdev.size = 256;
 	mc_dev->cdev.dev = dev;
 	mc_dev->cdev.ops = &mc_fops;
@@ -150,14 +235,30 @@ static int mc_probe(struct device_d *dev)
 	return 0;
 }
 
-static struct driver_d mc_driver = {
-	.name  = DRIVERNAME,
-	.probe = mc_probe,
+static int mc_i2c_probe(struct device_d *dev)
+{
+	return mc_probe(dev, MC13892_MODE_I2C);
+}
+
+static int mc_spi_probe(struct device_d *dev)
+{
+	return mc_probe(dev, MC13892_MODE_SPI);
+}
+
+static struct driver_d mc_i2c_driver = {
+	.name  = "mc13892-i2c",
+	.probe = mc_i2c_probe,
+};
+
+static struct driver_d mc_spi_driver = {
+	.name  = "mc13892-spi",
+	.probe = mc_spi_probe,
 };
 
 static int mc_init(void)
 {
-        register_driver(&mc_driver);
+        register_driver(&mc_i2c_driver);
+        register_driver(&mc_spi_driver);
         return 0;
 }