i2c: IHS I2C master driver

IHS I2C master support was merely a hack in the osd driver.
Now it is a proper u-boot I2C framework driver, supporting the
v2.00 master features.

Signed-off-by: Dirk Eibach <dirk.eibach@gdsys.cc>

2 files changed, 205 insertions, 0 deletions

diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index e33586d..96bd45d 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_SYS_I2C) += i2c_core.o
 obj-$(CONFIG_SYS_I2C_DAVINCI) += davinci_i2c.o
 obj-$(CONFIG_SYS_I2C_FSL) += fsl_i2c.o
 obj-$(CONFIG_SYS_I2C_FTI2C010) += fti2c010.o
+obj-$(CONFIG_SYS_I2C_IHS) += ihs_i2c.o
 obj-$(CONFIG_SYS_I2C_KONA) += kona_i2c.o
 obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
 obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
diff --git a/drivers/i2c/ihs_i2c.c b/drivers/i2c/ihs_i2c.c
new file mode 100644
index 0000000..ecc5856
--- /dev/null
+++ b/drivers/i2c/ihs_i2c.c
@@ -0,0 +1,204 @@
+/*
+ * (C) Copyright 2013
+ * Dirk Eibach,  Guntermann & Drunck GmbH, eibach@gdsys.de
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <gdsys_fpga.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+enum {
+	I2CINT_ERROR_EV = 1 << 13,
+	I2CINT_TRANSMIT_EV = 1 << 14,
+	I2CINT_RECEIVE_EV = 1 << 15,
+};
+
+enum {
+	I2CMB_WRITE = 1 << 10,
+	I2CMB_2BYTE = 1 << 11,
+	I2CMB_HOLD_BUS = 1 << 13,
+	I2CMB_NATIVE = 2 << 14,
+};
+
+static int wait_for_int(bool read)
+{
+	u16 val;
+	unsigned int ctr = 0;
+
+	FPGA_GET_REG(I2C_ADAP_HWNR, i2c.interrupt_status, &val);
+	while (!(val & (I2CINT_ERROR_EV
+	       | (read ? I2CINT_RECEIVE_EV : I2CINT_TRANSMIT_EV)))) {
+		udelay(10);
+		if (ctr++ > 5000) {
+			printf("I2C timeout\n");
+			return 1;
+		}
+		FPGA_GET_REG(I2C_ADAP_HWNR, i2c.interrupt_status, &val);
+	}
+
+	return (val & I2CINT_ERROR_EV) ? 1 : 0;
+}
+
+static int ihs_i2c_transfer(uchar chip, uchar *buffer, int len, bool read,
+			    bool is_last)
+{
+	u16 val;
+
+	FPGA_SET_REG(I2C_ADAP_HWNR, i2c.interrupt_status, I2CINT_ERROR_EV
+		     | I2CINT_RECEIVE_EV | I2CINT_TRANSMIT_EV);
+	FPGA_GET_REG(I2C_ADAP_HWNR, i2c.interrupt_status, &val);
+
+	if (!read && len) {
+		val = buffer[0];
+
+		if (len > 1)
+			val |= buffer[1] << 8;
+		FPGA_SET_REG(I2C_ADAP_HWNR, i2c.write_mailbox_ext, val);
+	}
+
+	FPGA_SET_REG(I2C_ADAP_HWNR, i2c.write_mailbox,
+		     I2CMB_NATIVE
+		     | (read ? 0 : I2CMB_WRITE)
+		     | (chip << 1)
+		     | ((len > 1) ? I2CMB_2BYTE : 0)
+		     | (is_last ? 0 : I2CMB_HOLD_BUS));
+
+	if (wait_for_int(read))
+		return 1;
+
+	if (read) {
+		FPGA_GET_REG(I2C_ADAP_HWNR, i2c.read_mailbox_ext, &val);
+		buffer[0] = val & 0xff;
+		if (len > 1)
+			buffer[1] = val >> 8;
+	}
+
+	return 0;
+}
+
+static int ihs_i2c_address(uchar chip, uint addr, int alen, bool hold_bus)
+{
+	int shift = (alen-1) * 8;
+
+	while (alen) {
+		int transfer = MIN(alen, 2);
+		uchar buf[2];
+		bool is_last = alen <= transfer;
+
+		buf[0] = addr >> shift;
+		if (alen > 1)
+			buf[1] = addr >> (shift - 8);
+
+		if (ihs_i2c_transfer(chip, buf, transfer, false,
+				     hold_bus ? false : is_last))
+			return 1;
+
+		shift -= 16;
+		alen -= transfer;
+	}
+
+	return 0;
+}
+
+static int ihs_i2c_access(struct i2c_adapter *adap, uchar chip, uint addr,
+			  int alen, uchar *buffer, int len, bool read)
+{
+	if (len <= 0)
+		return 1;
+
+	if (ihs_i2c_address(chip, addr, alen, !read))
+		return 1;
+
+	while (len) {
+		int transfer = MIN(len, 2);
+
+		if (ihs_i2c_transfer(chip, buffer, transfer, read,
+				     len <= transfer))
+			return 1;
+
+		buffer += transfer;
+		addr += transfer;
+		len -= transfer;
+	}
+
+	return 0;
+}
+
+
+static void ihs_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
+{
+#ifdef CONFIG_SYS_I2C_INIT_BOARD
+	/*
+	 * Call board specific i2c bus reset routine before accessing the
+	 * environment, which might be in a chip on that bus. For details
+	 * about this problem see doc/I2C_Edge_Conditions.
+	 */
+	i2c_init_board();
+#endif
+}
+
+static int ihs_i2c_probe(struct i2c_adapter *adap, uchar chip)
+{
+	uchar buffer[2];
+
+	if (ihs_i2c_transfer(chip, buffer, 0, true, true))
+		return 1;
+
+	return 0;
+}
+
+static int ihs_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
+			int alen, uchar *buffer, int len)
+{
+	return ihs_i2c_access(adap, chip, addr, alen, buffer, len, true);
+}
+
+static int ihs_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
+			 int alen, uchar *buffer, int len)
+{
+	return ihs_i2c_access(adap, chip, addr, alen, buffer, len, false);
+}
+
+static unsigned int ihs_i2c_set_bus_speed(struct i2c_adapter *adap,
+					     unsigned int speed)
+{
+	if (speed != adap->speed)
+		return 1;
+	return speed;
+}
+
+/*
+ * Register IHS i2c adapters
+ */
+#ifdef CONFIG_SYS_I2C_IHS_CH0
+U_BOOT_I2C_ADAP_COMPLETE(ihs0, ihs_i2c_init, ihs_i2c_probe,
+			 ihs_i2c_read, ihs_i2c_write,
+			 ihs_i2c_set_bus_speed,
+			 CONFIG_SYS_I2C_IHS_SPEED_0,
+			 CONFIG_SYS_I2C_IHS_SLAVE_0, 0)
+#endif
+#ifdef CONFIG_SYS_I2C_IHS_CH1
+U_BOOT_I2C_ADAP_COMPLETE(ihs1, ihs_i2c_init, ihs_i2c_probe,
+			 ihs_i2c_read, ihs_i2c_write,
+			 ihs_i2c_set_bus_speed,
+			 CONFIG_SYS_I2C_IHS_SPEED_1,
+			 CONFIG_SYS_I2C_IHS_SLAVE_1, 1)
+#endif
+#ifdef CONFIG_SYS_I2C_IHS_CH2
+U_BOOT_I2C_ADAP_COMPLETE(ihs2, ihs_i2c_init, ihs_i2c_probe,
+			 ihs_i2c_read, ihs_i2c_write,
+			 ihs_i2c_set_bus_speed,
+			 CONFIG_SYS_I2C_IHS_SPEED_2,
+			 CONFIG_SYS_I2C_IHS_SLAVE_2, 2)
+#endif
+#ifdef CONFIG_SYS_I2C_IHS_CH3
+U_BOOT_I2C_ADAP_COMPLETE(ihs3, ihs_i2c_init, ihs_i2c_probe,
+			 ihs_i2c_read, ihs_i2c_write,
+			 ihs_i2c_set_bus_speed,
+			 CONFIG_SYS_I2C_IHS_SPEED_3,
+			 CONFIG_SYS_I2C_IHS_SLAVE_3, 3)
+#endif