Add support for Maxim's DS4510 I2C device

Initial support for the DS4510, a CPU supervisor with
integrated EEPROM, SRAM, and 4 programmable non-volatile
GPIO pins. The CONFIG_DS4510 define enables support
for the device while the CONFIG_CMD_DS4510 define
enables the ds4510 command. The additional
CONFIG_DS4510_INFO, CONFIG_DS4510_MEM, and
CONFIG_DS4510_RST defines add additional sub-commands
to the ds4510 command when defined.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>

1 files changed, 424 insertions, 0 deletions

diff --git a/drivers/misc/ds4510.c b/drivers/misc/ds4510.c
new file mode 100644
index 0000000..4cd2fc2
--- /dev/null
+++ b/drivers/misc/ds4510.c
@@ -0,0 +1,424 @@
+/*
+ * 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 DS4510, a CPU supervisor with integrated EEPROM, SRAM,
+ * and 4 programmable non-volatile GPIO pins.
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <command.h>
+#include <ds4510.h>
+
+/* Default to an address that hopefully won't corrupt other i2c devices */
+#ifndef CONFIG_SYS_I2C_DS4510_ADDR
+#define CONFIG_SYS_I2C_DS4510_ADDR	(~0)
+#endif
+
+enum {
+	DS4510_CMD_INFO,
+	DS4510_CMD_DEVICE,
+	DS4510_CMD_NV,
+	DS4510_CMD_RSTDELAY,
+	DS4510_CMD_OUTPUT,
+	DS4510_CMD_INPUT,
+	DS4510_CMD_PULLUP,
+	DS4510_CMD_EEPROM,
+	DS4510_CMD_SEEPROM,
+	DS4510_CMD_SRAM,
+};
+
+/*
+ * Write to DS4510, taking page boundaries into account
+ */
+int ds4510_mem_write(uint8_t chip, int offset, uint8_t *buf, int count)
+{
+	int wrlen;
+	int i = 0;
+
+	do {
+		wrlen = DS4510_EEPROM_PAGE_SIZE -
+			DS4510_EEPROM_PAGE_OFFSET(offset);
+		if (count < wrlen)
+			wrlen = count;
+		if (i2c_write(chip, offset, 1, &buf[i], wrlen))
+			return -1;
+
+		/*
+		 * This delay isn't needed for SRAM writes but shouldn't delay
+		 * things too much, so do it unconditionally for simplicity
+		 */
+		udelay(DS4510_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
+		count -= wrlen;
+		offset += wrlen;
+		i += wrlen;
+	} while (count > 0);
+
+	return 0;
+}
+
+/*
+ * General read from DS4510
+ */
+int ds4510_mem_read(uint8_t chip, int offset, uint8_t *buf, int count)
+{
+	return i2c_read(chip, offset, 1, buf, count);
+}
+
+/*
+ * Write SEE bit in config register.
+ * nv = 0 - Writes to SEEPROM registers behave like EEPROM
+ * nv = 1 - Writes to SEEPROM registers behave like SRAM
+ */
+int ds4510_see_write(uint8_t chip, uint8_t nv)
+{
+	uint8_t data;
+
+	if (i2c_read(chip, DS4510_CFG, 1, &data, 1))
+		return -1;
+
+	if (nv)	/* Treat SEEPROM bits as EEPROM */
+		data &= ~DS4510_CFG_SEE;
+	else	/* Treat SEEPROM bits as SRAM */
+		data |= DS4510_CFG_SEE;
+
+	return ds4510_mem_write(chip, DS4510_CFG, &data, 1);
+}
+
+/*
+ * Write de-assertion of reset signal delay
+ */
+int ds4510_rstdelay_write(uint8_t chip, uint8_t delay)
+{
+	uint8_t data;
+
+	if (i2c_read(chip, DS4510_RSTDELAY, 1, &data, 1))
+		return -1;
+
+	data &= ~DS4510_RSTDELAY_MASK;
+	data |= delay & DS4510_RSTDELAY_MASK;
+
+	return ds4510_mem_write(chip, DS4510_RSTDELAY, &data, 1);
+}
+
+/*
+ * Write pullup characteristics of IO pins
+ */
+int ds4510_pullup_write(uint8_t chip, uint8_t val)
+{
+	val &= DS4510_IO_MASK;
+
+	return ds4510_mem_write(chip, DS4510_PULLUP, (uint8_t *)&val, 1);
+}
+
+/*
+ * Read pullup characteristics of IO pins
+ */
+int ds4510_pullup_read(uint8_t chip)
+{
+	uint8_t val;
+
+	if (i2c_read(chip, DS4510_PULLUP, 1, &val, 1))
+		return -1;
+
+	return val & DS4510_IO_MASK;
+}
+
+/*
+ * Write drive level of IO pins
+ */
+int ds4510_gpio_write(uint8_t chip, uint8_t val)
+{
+	uint8_t data;
+	int i;
+
+	for (i = 0; i < DS4510_NUM_IO; i++) {
+		if (i2c_read(chip, DS4510_IO0 - i, 1, &data, 1))
+			return -1;
+
+		if (val & (0x1 << i))
+			data |= 0x1;
+		else
+			data &= ~0x1;
+
+		if (ds4510_mem_write(chip, DS4510_IO0 - i, &data, 1))
+			return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Read drive level of IO pins
+ */
+int ds4510_gpio_read(uint8_t chip)
+{
+	uint8_t data;
+	int val = 0;
+	int i;
+
+	for (i = 0; i < DS4510_NUM_IO; i++) {
+		if (i2c_read(chip, DS4510_IO0 - i, 1, &data, 1))
+			return -1;
+
+		if (data & 1)
+			val |= (1 << i);
+	}
+
+	return val;
+}
+
+/*
+ * Read physical level of IO pins
+ */
+int ds4510_gpio_read_val(uint8_t chip)
+{
+	uint8_t val;
+
+	if (i2c_read(chip, DS4510_IO_STATUS, 1, &val, 1))
+		return -1;
+
+	return val & DS4510_IO_MASK;
+}
+
+#ifdef CONFIG_CMD_DS4510
+#ifdef CONFIG_CMD_DS4510_INFO
+/*
+ * Display DS4510 information
+ */
+static int ds4510_info(uint8_t chip)
+{
+	int i;
+	int tmp;
+	uint8_t data;
+
+	printf("DS4510 @ 0x%x:\n\n", chip);
+
+	if (i2c_read(chip, DS4510_RSTDELAY, 1, &data, 1))
+		return -1;
+	printf("rstdelay = 0x%x\n\n", data & DS4510_RSTDELAY_MASK);
+
+	if (i2c_read(chip, DS4510_CFG, 1, &data, 1))
+		return -1;
+	printf("config   = 0x%x\n", data);
+	printf(" /ready  = %d\n", data & DS4510_CFG_READY ? 1 : 0);
+	printf(" trip pt = %d\n", data & DS4510_CFG_TRIP_POINT ? 1 : 0);
+	printf(" rst sts = %d\n", data & DS4510_CFG_RESET ? 1 : 0);
+	printf(" /see    = %d\n", data & DS4510_CFG_SEE ? 1 : 0);
+	printf(" swrst   = %d\n\n", data & DS4510_CFG_SWRST ? 1 : 0);
+
+	printf("gpio pins: 3210\n");
+	printf("---------------\n");
+	printf("pullup     ");
+
+	tmp = ds4510_pullup_read(chip);
+	if (tmp == -1)
+		return tmp;
+	for (i = DS4510_NUM_IO - 1; i >= 0; i--)
+		printf("%d", (tmp & (1 << i)) ? 1 : 0);
+	printf("\n");
+
+	printf("driven     ");
+	tmp = ds4510_gpio_read(chip);
+	if (tmp == -1)
+		return -1;
+	for (i = DS4510_NUM_IO - 1; i >= 0; i--)
+		printf("%d", (tmp & (1 << i)) ? 1 : 0);
+	printf("\n");
+
+	printf("read       ");
+	tmp = ds4510_gpio_read_val(chip);
+	if (tmp == -1)
+		return -1;
+	for (i = DS4510_NUM_IO - 1; i >= 0; i--)
+		printf("%d", (tmp & (1 << i)) ? 1 : 0);
+	printf("\n");
+
+	return 0;
+}
+#endif /* CONFIG_CMD_DS4510_INFO */
+
+cmd_tbl_t cmd_ds4510[] = {
+	U_BOOT_CMD_MKENT(device, 3, 0, (void *)DS4510_CMD_DEVICE, "", ""),
+	U_BOOT_CMD_MKENT(nv, 3, 0, (void *)DS4510_CMD_NV, "", ""),
+	U_BOOT_CMD_MKENT(output, 4, 0, (void *)DS4510_CMD_OUTPUT, "", ""),
+	U_BOOT_CMD_MKENT(input, 3, 0, (void *)DS4510_CMD_INPUT, "", ""),
+	U_BOOT_CMD_MKENT(pullup, 4, 0, (void *)DS4510_CMD_PULLUP, "", ""),
+#ifdef CONFIG_CMD_DS4510_INFO
+	U_BOOT_CMD_MKENT(info, 2, 0, (void *)DS4510_CMD_INFO, "", ""),
+#endif
+#ifdef CONFIG_CMD_DS4510_RST
+	U_BOOT_CMD_MKENT(rstdelay, 3, 0, (void *)DS4510_CMD_RSTDELAY, "", ""),
+#endif
+#ifdef CONFIG_CMD_DS4510_MEM
+	U_BOOT_CMD_MKENT(eeprom, 6, 0, (void *)DS4510_CMD_EEPROM, "", ""),
+	U_BOOT_CMD_MKENT(seeprom, 6, 0, (void *)DS4510_CMD_SEEPROM, "", ""),
+	U_BOOT_CMD_MKENT(sram, 6, 0, (void *)DS4510_CMD_SRAM, "", ""),
+#endif
+};
+
+int do_ds4510(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+{
+	static uint8_t chip = CONFIG_SYS_I2C_DS4510_ADDR;
+	cmd_tbl_t *c;
+	ulong ul_arg2 = 0;
+	ulong ul_arg3 = 0;
+	int tmp;
+#ifdef CONFIG_CMD_DS4510_MEM
+	ulong addr;
+	ulong off;
+	ulong cnt;
+	int end;
+	int (*rw_func)(uint8_t, int, uint8_t *, int);
+#endif
+
+	c = find_cmd_tbl(argv[1], cmd_ds4510, ARRAY_SIZE(cmd_ds4510));
+
+	/* All commands but "device" require 'maxargs' arguments */
+	if (!c || !((argc == (c->maxargs)) ||
+		(((int)c->cmd == DS4510_CMD_DEVICE) &&
+		 (argc == (c->maxargs - 1))))) {
+		printf("Usage:\n%s\n", cmdtp->usage);
+		return 1;
+	}
+
+	/* arg2 used as chip addr and pin number */
+	if (argc > 2)
+		ul_arg2 = simple_strtoul(argv[2], NULL, 16);
+
+	/* arg3 used as output/pullup value */
+	if (argc > 3)
+		ul_arg3 = simple_strtoul(argv[3], NULL, 16);
+
+	switch ((int)c->cmd) {
+	case DS4510_CMD_DEVICE:
+		if (argc == 3)
+			chip = ul_arg2;
+		printf("Current device address: 0x%x\n", chip);
+		return 0;
+	case DS4510_CMD_NV:
+		return ds4510_see_write(chip, ul_arg2);
+	case DS4510_CMD_OUTPUT:
+		tmp = ds4510_gpio_read(chip);
+		if (tmp == -1)
+			return -1;
+		if (ul_arg3)
+			tmp |= (1 << ul_arg2);
+		else
+			tmp &= ~(1 << ul_arg2);
+		return ds4510_gpio_write(chip, tmp);
+	case DS4510_CMD_INPUT:
+		tmp = ds4510_gpio_read_val(chip);
+		if (tmp == -1)
+			return -1;
+		return (tmp & (1 << ul_arg2)) != 0;
+	case DS4510_CMD_PULLUP:
+		tmp = ds4510_pullup_read(chip);
+		if (tmp == -1)
+			return -1;
+		if (ul_arg3)
+			tmp |= (1 << ul_arg2);
+		else
+			tmp &= ~(1 << ul_arg2);
+		return ds4510_pullup_write(chip, tmp);
+#ifdef CONFIG_CMD_DS4510_INFO
+	case DS4510_CMD_INFO:
+		return ds4510_info(chip);
+#endif
+#ifdef CONFIG_CMD_DS4510_RST
+	case DS4510_CMD_RSTDELAY:
+		return ds4510_rstdelay_write(chip, ul_arg2);
+#endif
+#ifdef CONFIG_CMD_DS4510_MEM
+	case DS4510_CMD_EEPROM:
+		end = DS4510_EEPROM + DS4510_EEPROM_SIZE;
+		off = DS4510_EEPROM;
+		break;
+	case DS4510_CMD_SEEPROM:
+		end = DS4510_SEEPROM + DS4510_SEEPROM_SIZE;
+		off = DS4510_SEEPROM;
+		break;
+	case DS4510_CMD_SRAM:
+		end = DS4510_SRAM + DS4510_SRAM_SIZE;
+		off = DS4510_SRAM;
+		break;
+#endif
+	default:
+		/* We should never get here... */
+		return 1;
+	}
+
+#ifdef CONFIG_CMD_DS4510_MEM
+	/* Only eeprom, seeprom, and sram commands should make it here */
+	if (strcmp(argv[2], "read") == 0) {
+		rw_func = ds4510_mem_read;
+	} else if (strcmp(argv[2], "write") == 0) {
+		rw_func = ds4510_mem_write;
+	} else {
+		printf("Usage:\n%s\n", cmdtp->usage);
+		return 1;
+	}
+
+	addr = simple_strtoul(argv[3], NULL, 16);
+	off += simple_strtoul(argv[4], NULL, 16);
+	cnt = simple_strtoul(argv[5], NULL, 16);
+
+	if ((off + cnt) > end) {
+		printf("ERROR: invalid len\n");
+		return -1;
+	}
+
+	return rw_func(chip, off, (uint8_t *)addr, cnt);
+#endif
+}
+
+U_BOOT_CMD(
+	ds4510,	6,	1,	do_ds4510,
+	"ds4510	- ds4510 eeprom/seeprom/sram/gpio access\n",
+	"device [dev]\n"
+	"	- show or set current device address\n"
+#ifdef CONFIG_CMD_DS4510_INFO
+	"ds4510 info\n"
+	"	- display ds4510 info\n"
+#endif
+	"ds4510 output pin 0|1\n"
+	"	- set pin low or high-Z\n"
+	"ds4510 input pin\n"
+	"	- read value of pin\n"
+	"ds4510 pullup pin 0|1\n"
+	"	- disable/enable pullup on specified pin\n"
+	"ds4510 nv 0|1\n"
+	"	- make gpio and seeprom writes volatile/non-volatile\n"
+#ifdef CONFIG_CMD_DS4510_RST
+	"ds4510 rstdelay 0-3\n"
+	"	- set reset output delay\n"
+#endif
+#ifdef CONFIG_CMD_DS4510_MEM
+	"ds4510 eeprom read addr off cnt\n"
+	"ds4510 eeprom write addr off cnt\n"
+	"	- read/write 'cnt' bytes at EEPROM offset 'off'\n"
+	"ds4510 seeprom read addr off cnt\n"
+	"ds4510 seeprom write addr off cnt\n"
+	"	- read/write 'cnt' bytes at SRAM-shadowed EEPROM offset 'off'\n"
+	"ds4510 sram read addr off cnt\n"
+	"ds4510 sram write addr off cnt\n"
+	"	- read/write 'cnt' bytes at SRAM offset 'off'\n"
+#endif
+);
+#endif /* CONFIG_CMD_DS4510 */