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Diffstat (limited to 'src/roms/u-boot/drivers/gpio/pca9698.c')
-rw-r--r--src/roms/u-boot/drivers/gpio/pca9698.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/src/roms/u-boot/drivers/gpio/pca9698.c b/src/roms/u-boot/drivers/gpio/pca9698.c
new file mode 100644
index 0000000..3152bf6
--- /dev/null
+++ b/src/roms/u-boot/drivers/gpio/pca9698.c
@@ -0,0 +1,127 @@
+/*
+ * (C) Copyright 2011
+ * Dirk Eibach, Guntermann & Drunck GmbH, eibach@gdsys.de
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/*
+ * Driver for NXP's pca9698 40 bit I2C gpio expander
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <asm/errno.h>
+#include <pca9698.h>
+
+/*
+ * The pca9698 registers
+ */
+
+#define PCA9698_REG_INPUT 0x00
+#define PCA9698_REG_OUTPUT 0x08
+#define PCA9698_REG_POLARITY 0x10
+#define PCA9698_REG_CONFIG 0x18
+
+#define PCA9698_BUFFER_SIZE 5
+#define PCA9698_GPIO_COUNT 40
+
+static int pca9698_read40(u8 addr, u8 offset, u8 *buffer)
+{
+ u8 command = offset | 0x80; /* autoincrement */
+
+ return i2c_read(addr, command, 1, buffer, PCA9698_BUFFER_SIZE);
+}
+
+static int pca9698_write40(u8 addr, u8 offset, u8 *buffer)
+{
+ u8 command = offset | 0x80; /* autoincrement */
+
+ return i2c_write(addr, command, 1, buffer, PCA9698_BUFFER_SIZE);
+}
+
+static void pca9698_set_bit(unsigned gpio, u8 *buffer, unsigned value)
+{
+ unsigned byte = gpio / 8;
+ unsigned bit = gpio % 8;
+
+ if (value)
+ buffer[byte] |= (1 << bit);
+ else
+ buffer[byte] &= ~(1 << bit);
+}
+
+int pca9698_request(unsigned gpio, const char *label)
+{
+ if (gpio >= PCA9698_GPIO_COUNT)
+ return -EINVAL;
+
+ return 0;
+}
+
+void pca9698_free(unsigned gpio)
+{
+}
+
+int pca9698_direction_input(u8 addr, unsigned gpio)
+{
+ u8 data[PCA9698_BUFFER_SIZE];
+ int res;
+
+ res = pca9698_read40(addr, PCA9698_REG_CONFIG, data);
+ if (res)
+ return res;
+
+ pca9698_set_bit(gpio, data, 1);
+
+ return pca9698_write40(addr, PCA9698_REG_CONFIG, data);
+}
+
+int pca9698_direction_output(u8 addr, unsigned gpio, int value)
+{
+ u8 data[PCA9698_BUFFER_SIZE];
+ int res;
+
+ res = pca9698_set_value(addr, gpio, value);
+ if (res)
+ return res;
+
+ res = pca9698_read40(addr, PCA9698_REG_CONFIG, data);
+ if (res)
+ return res;
+
+ pca9698_set_bit(gpio, data, 0);
+
+ return pca9698_write40(addr, PCA9698_REG_CONFIG, data);
+}
+
+int pca9698_get_value(u8 addr, unsigned gpio)
+{
+ unsigned config_byte = gpio / 8;
+ unsigned config_bit = gpio % 8;
+ unsigned value;
+ u8 data[PCA9698_BUFFER_SIZE];
+ int res;
+
+ res = pca9698_read40(addr, PCA9698_REG_INPUT, data);
+ if (res)
+ return -1;
+
+ value = data[config_byte] & (1 << config_bit);
+
+ return !!value;
+}
+
+int pca9698_set_value(u8 addr, unsigned gpio, int value)
+{
+ u8 data[PCA9698_BUFFER_SIZE];
+ int res;
+
+ res = pca9698_read40(addr, PCA9698_REG_OUTPUT, data);
+ if (res)
+ return res;
+
+ pca9698_set_bit(gpio, data, value);
+
+ return pca9698_write40(addr, PCA9698_REG_OUTPUT, data);
+}
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