[U-Boot] [PATCH 1/3] Add support for PCA953x I2C gpio devices
Peter Tyser
ptyser at xes-inc.com
Fri Oct 24 00:23:57 CEST 2008
Initial support for NXP's 4 and 8 bit I2C gpio expanders
(eg pca9537, pca9557, etc). The CONFIG_PCA953X define
enables support for the devices while the CONFIG_CMD_PCA953X
define enables the pca953x command.
Signed-off-by: Peter Tyser <ptyser at xes-inc.com>
---
Makefile | 2 +
README | 7 ++
drivers/gpio/Makefile | 47 ++++++++++++
drivers/gpio/pca953x.c | 186 ++++++++++++++++++++++++++++++++++++++++++++++++
include/gpio/pca953x.h | 39 ++++++++++
5 files changed, 281 insertions(+), 0 deletions(-)
create mode 100644 drivers/gpio/Makefile
create mode 100644 drivers/gpio/pca953x.c
create mode 100644 include/gpio/pca953x.h
diff --git a/Makefile b/Makefile
index fceb8a2..40c08a7 100644
--- a/Makefile
+++ b/Makefile
@@ -221,6 +221,7 @@ LIBS += disk/libdisk.a
LIBS += drivers/bios_emulator/libatibiosemu.a
LIBS += drivers/block/libblock.a
LIBS += drivers/dma/libdma.a
+LIBS += drivers/gpio/libgpio.a
LIBS += drivers/hwmon/libhwmon.a
LIBS += drivers/i2c/libi2c.a
LIBS += drivers/input/libinput.a
@@ -396,6 +397,7 @@ TAG_SUBDIRS += disk
TAG_SUBDIRS += common
TAG_SUBDIRS += drivers/bios_emulator
TAG_SUBDIRS += drivers/block
+TAG_SUBDIRS += drivers/gpio
TAG_SUBDIRS += drivers/hwmon
TAG_SUBDIRS += drivers/i2c
TAG_SUBDIRS += drivers/input
diff --git a/README b/README
index ebee20f..73bed41 100644
--- a/README
+++ b/README
@@ -601,6 +601,7 @@ The following options need to be configured:
CONFIG_CMD_MII * MII utility commands
CONFIG_CMD_NAND * NAND support
CONFIG_CMD_NET bootp, tftpboot, rarpboot
+ CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
CONFIG_CMD_PCI * pciinfo
CONFIG_CMD_PCMCIA * PCMCIA support
CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
@@ -678,6 +679,12 @@ The following options need to be configured:
Note that if the RTC uses I2C, then the I2C interface
must also be configured. See I2C Support, below.
+- GPIO Support:
+ CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
+
+ Note that if the GPIO device uses I2C, then the I2C interface
+ must also be configured. See I2C Support, below.
+
- Timestamp Support:
When CONFIG_TIMESTAMP is selected, the timestamp
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
new file mode 100644
index 0000000..dd618ed
--- /dev/null
+++ b/drivers/gpio/Makefile
@@ -0,0 +1,47 @@
+#
+# Copyright 2000-2008
+# Wolfgang Denk, DENX Software Engineering, wd at denx.de.
+#
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+#
+
+include $(TOPDIR)/config.mk
+
+LIB := $(obj)libgpio.a
+
+COBJS-$(CONFIG_PCA953X) += pca953x.o
+
+COBJS := $(COBJS-y)
+SRCS := $(COBJS:.o=.c)
+OBJS := $(addprefix $(obj),$(COBJS))
+
+all: $(LIB)
+
+$(LIB): $(obj).depend $(OBJS)
+ $(AR) $(ARFLAGS) $@ $(OBJS)
+
+
+#########################################################################
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+########################################################################
diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
new file mode 100644
index 0000000..317241a
--- /dev/null
+++ b/drivers/gpio/pca953x.c
@@ -0,0 +1,186 @@
+/*
+ * Copyright 2008 Extreme Engineering Solutions, Inc.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/*
+ * 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
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <gpio/pca953x.h>
+
+/*
+ * Modify masked bits in register
+ */
+static int pca953x_reg_write(uint8_t chip, uint addr, uint mask, uint data)
+{
+ uint8_t val;
+
+ if (i2c_read(chip, addr, 1, &val, 1))
+ return -1;
+
+ val &= ~mask;
+ val |= data;
+
+ return i2c_write(chip, addr, 1, &val, 1);
+}
+
+/*
+ * Set output value of IO pins in 'mask' to corresponding value in 'data'
+ * 0 = low, 1 = high
+ */
+int pca953x_set_val(uint8_t chip, uint mask, uint data)
+{
+ return pca953x_reg_write(chip, PCA953X_OUT, mask, data);
+}
+
+/*
+ * Set read polarity of IO pins in 'mask' to corresponding value in 'data'
+ * 0 = read pin value, 1 = read inverted pin value
+ */
+int pca953x_set_pol(uint8_t chip, uint mask, uint data)
+{
+ return pca953x_reg_write(chip, PCA953X_POL, mask, data);
+}
+
+/*
+ * Set direction of IO pins in 'mask' to corresponding value in 'data'
+ * 0 = output, 1 = input
+ */
+int pca953x_set_dir(uint8_t chip, uint mask, uint data)
+{
+ return pca953x_reg_write(chip, PCA953X_CONF, mask, data);
+}
+
+/*
+ * Read current logic level of all IO pins
+ */
+int pca953x_get_val(uint8_t chip)
+{
+ uint8_t val;
+
+ if (i2c_read(chip, 0, 1, &val, 1))
+ return -1;
+
+ return (int)val;
+}
+
+#ifdef CONFIG_CMD_PCA953X
+/*
+ * Display pca953x information
+ */
+static int pca953x_info(uint8_t chip)
+{
+ int i;
+ uint8_t data;
+
+ printf("pca953x@ 0x%x:\n\n", chip);
+ printf("gpio pins: 76543210\n");
+ printf("-------------------\n");
+
+ i2c_read(chip, PCA953X_CONF, 1, &data, 1);
+ printf("conf: ");
+ for (i = 7; i >= 0; i--)
+ printf("%c", data & (1 << i) ? 'i' : 'o');
+ printf("\n");
+
+ i2c_read(chip, PCA953X_POL, 1, &data, 1);
+ printf("invert: ");
+ for (i = 7; i >= 0; i--)
+ printf("%c", data & (1 << i) ? '1' : '0');
+ printf("\n");
+
+ i2c_read(chip, PCA953X_IN, 1, &data, 1);
+ printf("input: ");
+ for (i = 7; i >= 0; i--)
+ printf("%c", data & (1 << i) ? '1' : '0');
+ printf("\n");
+
+ i2c_read(chip, PCA953X_OUT, 1, &data, 1);
+ printf("output: ");
+ for (i = 7; i >= 0; i--)
+ printf("%c", data & (1 << i) ? '1' : '0');
+ printf("\n");
+
+ return 0;
+}
+
+int do_pca953x(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+{
+ int val;
+ uint8_t chip;
+ ulong pin;
+
+ chip = (uint8_t)simple_strtoul(argv[1], NULL, 16);
+
+ if (i2c_probe(chip)) {
+ printf("I2C device 0x%02x not found\n", chip);
+ return -1;
+ }
+
+ switch (argc) {
+ case 3:
+ if (strcmp(argv[2], "info") == 0)
+ return pca953x_info(chip);
+ break;
+ case 4:
+ if (strcmp(argv[2], "input") != 0)
+ break;
+
+ pin = simple_strtoul(argv[3], NULL, 16);
+
+ pca953x_set_dir(chip, (1 << pin), PCA953X_DIR_IN << pin);
+ val = (pca953x_get_val(chip) & (1 << pin)) != 0;
+
+ printf("chip 0x%02x, pin 0x%lx = %d\n", chip, pin, val);
+ return val;
+ case 5:
+ pin = simple_strtoul(argv[3], NULL, 16);
+ val = simple_strtoul(argv[4], NULL, 16) & 0x1;
+
+ if (strcmp(argv[2], "output") == 0) {
+ pca953x_set_dir(chip, (1 << pin),
+ (PCA953X_DIR_OUT << pin));
+ return pca953x_set_val(chip, (1 << pin), (val << pin));
+ } else if (strcmp(argv[2], "invert") == 0) {
+ return pca953x_set_pol(chip, (1 << pin), (val << pin));
+ }
+ break;
+ default:
+ break;
+ }
+
+ printf("Usage:\n%s\n", cmdtp->usage);
+ return 1;
+}
+
+U_BOOT_CMD(
+ pca953x, 6, 2, do_pca953x,
+ "pca953x - pca953x gpio access\n",
+ "chip info\n"
+ " - display info for chip\n"
+ "pca953x chip output pin 0|1\n"
+ " - set pin as output and drive low or high\n"
+ "pca953x chip invert pin 0|1\n"
+ " - disable/enable polarity inversion for reads\n"
+ "pca953x chip intput pin\n"
+ " - set pin as input and read value\n"
+);
+
+#endif /* CONFIG_CMD_PCA953X */
diff --git a/include/gpio/pca953x.h b/include/gpio/pca953x.h
new file mode 100644
index 0000000..6c2b58c
--- /dev/null
+++ b/include/gpio/pca953x.h
@@ -0,0 +1,39 @@
+/*
+ * Copyright 2008 Extreme Engineering Solutions, Inc.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef __PCA953X_H_
+#define __PCA953X_H_
+
+#define PCA953X_IN 0x00
+#define PCA953X_OUT 0x01
+#define PCA953X_POL 0x02
+#define PCA953X_CONF 0x03
+
+#define PCA953X_OUT_LOW 0
+#define PCA953X_OUT_HIGH 1
+#define PCA953X_POL_NORMAL 0
+#define PCA953X_POL_INVERT 1
+#define PCA953X_DIR_OUT 0
+#define PCA953X_DIR_IN 1
+
+int pca953x_set_val(u8 chip, uint mask, uint data);
+int pca953x_set_pol(u8 chip, uint mask, uint data);
+int pca953x_set_dir(u8 chip, uint mask, uint data);
+int pca953x_get_val(u8 chip);
+
+#endif /* __PCA953X_H_ */
--
1.6.0.2.GIT
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