new PCA9564 i2c bridge driver

Signed-off-by: Valentin Yakovenkov <yakovenkov@niistt.ru>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

1 files changed, 189 insertions, 0 deletions

diff --git a/drivers/i2c/pca9564_i2c.c b/drivers/i2c/pca9564_i2c.c
new file mode 100644
index 0000000..199a9ee
--- /dev/null
+++ b/drivers/i2c/pca9564_i2c.c
@@ -0,0 +1,189 @@
+/*
+ * File:         drivers/i2c/pca9564.c
+ * Based on:     drivers/i2c/s3c44b0_i2c.c
+ * Author:
+ *
+ * Created:      2009-06-23
+ * Description:  PCA9564 i2c bridge driver
+ *
+ * Modified:
+ *               Copyright 2009 CJSC "NII STT", http://www.niistt.ru/
+ *
+ * Bugs:
+ *
+ * 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, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <pca9564.h>
+#include <asm/io.h>
+
+#define PCA_STA			(CONFIG_PCA9564_BASE + 0)
+#define PCA_TO			(CONFIG_PCA9564_BASE + 0)
+#define PCA_DAT			(CONFIG_PCA9564_BASE + (1 << 2))
+#define PCA_ADR			(CONFIG_PCA9564_BASE + (2 << 2))
+#define PCA_CON			(CONFIG_PCA9564_BASE + (3 << 2))
+
+static unsigned char pca_read_reg(unsigned int reg)
+{
+	return readb((void *)reg);
+}
+
+static void pca_write_reg(unsigned int reg, unsigned char value)
+{
+	writeb(value, (void *)reg);
+}
+
+static int pca_wait_busy(void)
+{
+	unsigned int timeout = 10000;
+
+	while (!(pca_read_reg(PCA_CON) & PCA_CON_SI) && --timeout)
+		udelay(1);
+
+	if (timeout == 0)
+		debug("I2C timeout!\n");
+
+	debug("CON = 0x%02x, STA = 0x%02x\n", pca_read_reg(PCA_CON),
+	       pca_read_reg(PCA_STA));
+
+	return timeout ? 0 : 1;
+}
+
+/*=====================================================================*/
+/*                         Public Functions                            */
+/*=====================================================================*/
+
+/*-----------------------------------------------------------------------
+ * Initialization
+ */
+void i2c_init(int speed, int slaveaddr)
+{
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO | speed);
+}
+
+/*
+ * Probe the given I2C chip address.  Returns 0 if a chip responded,
+ * not 0 on failure.
+ */
+
+int i2c_probe(uchar chip)
+{
+	unsigned char res;
+
+	pca_write_reg(PCA_CON, PCA_CON_STA | PCA_CON_ENSIO);
+	pca_wait_busy();
+
+	pca_write_reg(PCA_CON, PCA_CON_STA | PCA_CON_ENSIO);
+
+	pca_write_reg(PCA_DAT, (chip << 1) | 1);
+	res = pca_wait_busy();
+
+	if ((res == 0) && (pca_read_reg(PCA_STA) == 0x48))
+		res = 1;
+
+	pca_write_reg(PCA_CON, PCA_CON_STO | PCA_CON_ENSIO);
+
+	return res;
+}
+
+/*
+ * Read/Write interface:
+ *   chip:    I2C chip address, range 0..127
+ *   addr:    Memory (register) address within the chip
+ *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
+ *              memories, 0 for register type devices with only one
+ *              register)
+ *   buffer:  Where to read/write the data
+ *   len:     How many bytes to read/write
+ *
+ *   Returns: 0 on success, not 0 on failure
+ */
+int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
+{
+	int i;
+
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STA);
+	pca_wait_busy();
+
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+
+	pca_write_reg(PCA_DAT, (chip << 1));
+	pca_wait_busy();
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+
+	if (alen > 0) {
+		pca_write_reg(PCA_DAT, addr);
+		pca_wait_busy();
+		pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+	}
+
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STO);
+
+	udelay(500);
+
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STA);
+	pca_wait_busy();
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+
+	pca_write_reg(PCA_DAT, (chip << 1) | 1);
+	pca_wait_busy();
+
+	for (i = 0; i < len; ++i) {
+		if (i == len - 1)
+			pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+		else
+			pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_AA);
+
+		pca_wait_busy();
+		buffer[i] = pca_read_reg(PCA_DAT);
+
+	}
+
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STO);
+
+	return 0;
+}
+
+int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
+{
+	int i;
+
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STA);
+	pca_wait_busy();
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+
+	pca_write_reg(PCA_DAT, chip << 1);
+	pca_wait_busy();
+	pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+
+	if (alen > 0) {
+		pca_write_reg(PCA_DAT, addr);
+		pca_wait_busy();
+		pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+	}
+
+	for (i = 0; i < len; ++i) {
+		pca_write_reg(PCA_DAT, buffer[i]);
+		pca_wait_busy();
+		pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+	}
+
+	pca_write_reg(PCA_CON, PCA_CON_STO | PCA_CON_ENSIO);
+
+	return 0;
+}