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authorWolfgang Denk <wd@denx.de>2012-07-31 22:07:42 +0200
committerWolfgang Denk <wd@denx.de>2012-07-31 22:07:42 +0200
commit948fa1713cce09dd958bda41eb5c97015a217f91 (patch)
tree26ccc8735233389f214af564a4bfc75a7e041668 /arch/arm/cpu/armv7/imx-common/i2c.c
parentd978780b2e676c005460cd561f4f15b5220bdf49 (diff)
parente69e482bbf16795539af112d6a21d4ddaee35105 (diff)
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Merge branch 'master' of git://git.denx.de/u-boot-i2c
* 'master' of git://git.denx.de/u-boot-i2c: km/common: remove printfs for i2c deblocking code CONFIG: SMDK5250: I2C: Enable I2C I2C: Add support for Multi channel I2C: Modify the I2C driver for EXYNOS5 I2C: Move struct s3c24x0_i2c to a common place. EXYNOS: PINMUX: Add pinmux support for I2C EXYNOS5: define EXYNOS5_I2C_SPACING EXYNOS: Add I2C base address. EXYNOS: CLK: Add i2c clock mx6qsabrelite: add i2c multi-bus support imx-common: add i2c.c for bus recovery support i.mx53: add definition for I2C3_BASE_ADDR i.mx: iomux-v3.c: move to imx-common directory i.mx: iomux-v3.h: move to imx-common include directory iomux-v3: remove include of mx6x_pins.h mxc_i2c: finish adding CONFIG_I2C_MULTI_BUS support mxc_i2c: add bus recovery support mxc_i2c: prep work for multiple busses support mxc_i2c: add i2c_regs argument to i2c_imx_stop mxc_i2c: add retries mxc_i2c: check for arbitration lost mxc_i2c: change slave addr if conflicts with destination. mxc_i2c: don't disable controller after every transaction mxc_i2c: place i2c_reset code inline mxc_i2c: place imx_start code inline mxc_i2c: remove redundant read mxc_i2c: combine i2c_imx_bus_busy and i2c_imx_trx_complete into wait_for_sr_state mxc_i2c.c: code i2c_probe as a 0 length i2c_write mxc_i2c: call i2c_imx_stop on error in i2c_read/i2c_write mxc_i2c: create i2c_init_transfer mxc_i2c: clear i2sr before waiting for bit mxc_i2c: create tx_byte function mxc_i2c: remove ifdef of CONFIG_HARD_I2C mxc_i2c: fix i2c_imx_stop i2c: deblock i2c bus also if accessed before realocation Signed-off-by: Wolfgang Denk <wd@denx.de>
Diffstat (limited to 'arch/arm/cpu/armv7/imx-common/i2c.c')
-rw-r--r--arch/arm/cpu/armv7/imx-common/i2c.c99
1 files changed, 99 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/imx-common/i2c.c b/arch/arm/cpu/armv7/imx-common/i2c.c
new file mode 100644
index 0000000..da2b26f
--- /dev/null
+++ b/arch/arm/cpu/armv7/imx-common/i2c.c
@@ -0,0 +1,99 @@
+/*
+ * Copyright (C) 2012 Boundary Devices Inc.
+ *
+ * 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 <common.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/errno.h>
+#include <asm/gpio.h>
+#include <asm/imx-common/mxc_i2c.h>
+#include <watchdog.h>
+
+static int force_idle_bus(void *priv)
+{
+ int i;
+ int sda, scl;
+ ulong elapsed, start_time;
+ struct i2c_pads_info *p = (struct i2c_pads_info *)priv;
+ int ret = 0;
+
+ gpio_direction_input(p->sda.gp);
+ gpio_direction_input(p->scl.gp);
+
+ imx_iomux_v3_setup_pad(p->sda.gpio_mode);
+ imx_iomux_v3_setup_pad(p->scl.gpio_mode);
+
+ sda = gpio_get_value(p->sda.gp);
+ scl = gpio_get_value(p->scl.gp);
+ if ((sda & scl) == 1)
+ goto exit; /* Bus is idle already */
+
+ printf("%s: sda=%d scl=%d sda.gp=0x%x scl.gp=0x%x\n", __func__,
+ sda, scl, p->sda.gp, p->scl.gp);
+ /* Send high and low on the SCL line */
+ for (i = 0; i < 9; i++) {
+ gpio_direction_output(p->scl.gp, 0);
+ udelay(50);
+ gpio_direction_input(p->scl.gp);
+ udelay(50);
+ }
+ start_time = get_timer(0);
+ for (;;) {
+ sda = gpio_get_value(p->sda.gp);
+ scl = gpio_get_value(p->scl.gp);
+ if ((sda & scl) == 1)
+ break;
+ WATCHDOG_RESET();
+ elapsed = get_timer(start_time);
+ if (elapsed > (CONFIG_SYS_HZ / 5)) { /* .2 seconds */
+ ret = -EBUSY;
+ printf("%s: failed to clear bus, sda=%d scl=%d\n",
+ __func__, sda, scl);
+ break;
+ }
+ }
+exit:
+ imx_iomux_v3_setup_pad(p->sda.i2c_mode);
+ imx_iomux_v3_setup_pad(p->scl.i2c_mode);
+ return ret;
+}
+
+static void * const i2c_bases[] = {
+ (void *)I2C1_BASE_ADDR,
+ (void *)I2C2_BASE_ADDR,
+#ifdef I2C3_BASE_ADDR
+ (void *)I2C3_BASE_ADDR,
+#endif
+};
+
+/* i2c_index can be from 0 - 2 */
+void setup_i2c(unsigned i2c_index, int speed, int slave_addr,
+ struct i2c_pads_info *p)
+{
+ if (i2c_index >= ARRAY_SIZE(i2c_bases))
+ return;
+ /* Enable i2c clock */
+ enable_i2c_clk(1, i2c_index);
+ /* Make sure bus is idle */
+ force_idle_bus(p);
+ bus_i2c_init(i2c_bases[i2c_index], speed, slave_addr,
+ force_idle_bus, p);
+}