This adds support for for the PCA9535/PCA9539 family of gpio devices which
have 16 output pins.
To let the driver know which devices are 16-pin it is necessary to define
CONFIG_SYS_I2C_PCA953X_WIDTH in your board config file. This is used to
create an array of {chip, ngpio} tuples that are used to determine the
width of a particular chip. For backwards compatibility it is assumed that
any chip not defined in CONFIG_SYS_I2C_PCA953X_WIDTH has 8 pins.
Signed-off-by: Chris Packham chris.pack...@alliedtelesis.co.nz
---
Changes since v2:
- I've addressed Peters style comments.
- I've added a blurb to README describing the new config option
README |4 ++
drivers/gpio/pca953x.c | 111 ++--
2 files changed, 92 insertions(+), 23 deletions(-)
diff --git a/README b/README
index 68f5fb0..831c5af 100644
--- a/README
+++ b/README
@@ -746,6 +746,10 @@ The following options need to be configured:
CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
CONFIG_PCA953X_INFO - enable pca953x info command
+ The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
+ chip-ngpio pairs that tell the PCA953X driver the number of
+ pins supported by a particular chip.
+
Note that if the GPIO device uses I2C, then the I2C interface
must also be configured. See I2C Support, below.
diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
index 6e82bd6..c8f5403 100644
--- a/drivers/gpio/pca953x.c
+++ b/drivers/gpio/pca953x.c
@@ -17,8 +17,8 @@
*/
/*
- * Driver for NXP's 4 and 8 bit I2C gpio expanders (eg pca9537, pca9557, etc)
- * TODO: support additional devices with more than 8-bits GPIO
+ * Driver for NXP's 4, 8 and 16 bit I2C gpio expanders (eg pca9537, pca9557,
+ * pca9539, etc)
*/
#include common.h
@@ -38,20 +38,78 @@ enum {
PCA953X_CMD_INVERT,
};
+#ifdef CONFIG_SYS_I2C_PCA953X_WIDTH
+struct pca953x_chip_ngpio {
+ uint8_t chip;
+ uint8_t ngpio;
+};
+
+static struct pca953x_chip_ngpio pca953x_chip_ngpios[] =
+CONFIG_SYS_I2C_PCA953X_WIDTH;
+
+#define NUM_CHIP_GPIOS (sizeof(pca953x_chip_ngpios) / \
+ sizeof(struct pca953x_chip_ngpio))
+
+/*
+ * Determine the number of GPIO pins supported. If we don't know we assume
+ * 8 pins.
+ */
+static int pca953x_ngpio(uint8_t chip)
+{
+ int i;
+
+ for (i = 0; i NUM_CHIP_GPIOS; i++)
+ if (pca953x_chip_ngpios[i].chip == chip)
+ return pca953x_chip_ngpios[i].ngpio;
+
+ return 8;
+}
+#else
+#define pca953x_ngpio(chip)8
+#endif
+
/*
* Modify masked bits in register
*/
static int pca953x_reg_write(uint8_t chip, uint addr, uint mask, uint data)
{
- uint8_t val;
+ uint8_t valb;
+ uint16_t valw;
- if (i2c_read(chip, addr, 1, val, 1))
- return -1;
+ if (pca953x_ngpio(chip) = 8) {
+ if (i2c_read(chip, addr, 1, valb, 1))
+ return -1;
+
+ valb = ~mask;
+ valb |= data;
+
+ return i2c_write(chip, addr, 1, valb, 1);
+ } else {
+ if (i2c_read(chip, addr 1, 1, (u8*)valw, 2))
+ return -1;
+
+ valw = ~mask;
+ valw |= data;
+
+ return i2c_write(chip, addr 1, 1, (u8*)valw, 2);
+ }
+}
- val = ~mask;
- val |= data;
+static int pca953x_reg_read(uint8_t chip, uint addr, uint *data)
+{
+ uint8_t valb;
+ uint16_t valw;
- return i2c_write(chip, addr, 1, val, 1);
+ if (pca953x_ngpio(chip) = 8) {
+ if (i2c_read(chip, addr, 1, valb, 1))
+ return -1;
+ *data = (int)valb;
+ } else {
+ if (i2c_read(chip, addr 1, 1, (u8*)valw, 2))
+ return -1;
+ *data = (int)valw;
+ }
+ return 0;
}
/*
@@ -86,9 +144,9 @@ int pca953x_set_dir(uint8_t chip, uint mask, uint data)
*/
int pca953x_get_val(uint8_t chip)
{
- uint8_t val;
+ uint val;
- if (i2c_read(chip, 0, 1, val, 1))
+ if (pca953x_reg_read(chip, PCA953X_IN, val) 0)
return -1;
return (int)val;
@@ -102,37 +160,44 @@ int pca953x_get_val(uint8_t chip)
static int pca953x_info(uint8_t chip)
{
int i;
- uint8_t data;
+ uint data;
+ int nr_gpio = pca953x_ngpio(chip);
+ int msb = nr_gpio - 1;
- printf(pca953x@ 0x%x:\n\n, chip);
- printf(gpio pins: 76543210\n);
- printf(---\n);
+ printf(pca953x@ 0x%x (%d pins):\n\n, chip, nr_gpio);
+ printf(gpio pins: );
+ for (i = msb; i = 0; i--)
+ printf(%x, i);
+ printf(\n);
+ for (i = 11 + nr_gpio; i 0; i--)
+ printf(-);
+ printf(\n);
- if (i2c_read(chip, PCA953X_CONF, 1, data, 1))
+ if
