-From 3c5032fe34f1af50e9e5fe58d40bf93c1717302f Mon Sep 17 00:00:00 2001
+From 659aa30c59fb188b533a7edcb9bd38ac007a2739 Mon Sep 17 00:00:00 2001
From: Yangbo Lu <yangbo.lu@nxp.com>
-Date: Mon, 25 Sep 2017 12:19:53 +0800
-Subject: [PATCH] i2c: support layerscape
+Date: Wed, 17 Jan 2018 15:35:11 +0800
+Subject: [PATCH 21/30] i2c: support layerscape
-This is a integrated patch for layerscape i2c support.
+This is an integrated patch for layerscape i2c support.
Signed-off-by: Zhang Ying-22455 <ying.zhang22455@nxp.com>
Signed-off-by: Priyanka Jain <Priyanka.Jain@freescale.com>
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
---
- drivers/i2c/busses/i2c-imx.c | 10 ++++++++-
- drivers/i2c/muxes/i2c-mux-pca954x.c | 43 +++++++++++++++++++++++++++++++++++++
- 2 files changed, 52 insertions(+), 1 deletion(-)
+ drivers/i2c/busses/i2c-imx.c | 195 +++++++++++++++++++++++++++++++++++-
+ drivers/i2c/muxes/i2c-mux-pca954x.c | 43 ++++++++
+ 2 files changed, 237 insertions(+), 1 deletion(-)
-diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
-index 47fc1f1a..a35c366b 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
-@@ -889,6 +889,14 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter,
+@@ -53,6 +53,11 @@
+ #include <linux/pm_runtime.h>
+ #include <linux/sched.h>
+ #include <linux/slab.h>
++#include <linux/gpio.h>
++#include <linux/of_address.h>
++#include <linux/of.h>
++#include <linux/of_device.h>
++#include <linux/libata.h>
+
+ /* This will be the driver name the kernel reports */
+ #define DRIVER_NAME "imx-i2c"
+@@ -117,6 +122,54 @@
+
+ #define I2C_PM_TIMEOUT 10 /* ms */
+
++enum pinmux_endian_type {
++ BIG_ENDIAN,
++ LITTLE_ENDIAN,
++};
++
++struct pinmux_cfg {
++ enum pinmux_endian_type endian; /* endian of RCWPMUXCR0 */
++ u32 pmuxcr_offset;
++ u32 pmuxcr_set_bit; /* pin mux of RCWPMUXCR0 */
++};
++
++static struct pinmux_cfg ls1012a_pinmux_cfg = {
++ .endian = BIG_ENDIAN,
++ .pmuxcr_offset = 0x430,
++ .pmuxcr_set_bit = 0x10,
++};
++
++static struct pinmux_cfg ls1043a_pinmux_cfg = {
++ .endian = BIG_ENDIAN,
++ .pmuxcr_offset = 0x40C,
++ .pmuxcr_set_bit = 0x10,
++};
++
++static struct pinmux_cfg ls1046a_pinmux_cfg = {
++ .endian = BIG_ENDIAN,
++ .pmuxcr_offset = 0x40C,
++ .pmuxcr_set_bit = 0x80000000,
++};
++
++static const struct of_device_id pinmux_of_match[] = {
++ { .compatible = "fsl,ls1012a-vf610-i2c", .data = &ls1012a_pinmux_cfg},
++ { .compatible = "fsl,ls1043a-vf610-i2c", .data = &ls1043a_pinmux_cfg},
++ { .compatible = "fsl,ls1046a-vf610-i2c", .data = &ls1046a_pinmux_cfg},
++ {},
++};
++MODULE_DEVICE_TABLE(of, pinmux_of_match);
++
++/* The SCFG, Supplemental Configuration Unit, provides SoC specific
++ * configuration and status registers for the device. There is a
++ * SDHC IO VSEL control register on SCFG for some platforms. It's
++ * used to support SDHC IO voltage switching.
++ */
++static const struct of_device_id scfg_device_ids[] = {
++ { .compatible = "fsl,ls1012a-scfg", },
++ { .compatible = "fsl,ls1043a-scfg", },
++ { .compatible = "fsl,ls1046a-scfg", },
++ {}
++};
+ /*
+ * sorted list of clock divider, register value pairs
+ * taken from table 26-5, p.26-9, Freescale i.MX
+@@ -210,6 +263,12 @@ struct imx_i2c_struct {
+ struct pinctrl_state *pinctrl_pins_gpio;
+
+ struct imx_i2c_dma *dma;
++ int layerscape_bus_recover;
++ int gpio;
++ int need_set_pmuxcr;
++ int pmuxcr_set;
++ int pmuxcr_endian;
++ void __iomem *pmuxcr_addr;
+ };
+
+ static const struct imx_i2c_hwdata imx1_i2c_hwdata = {
+@@ -879,6 +938,78 @@ static int i2c_imx_read(struct imx_i2c_s
+ return 0;
+ }
+
++/*
++ * Based on the I2C specification, if the data line (SDA) is
++ * stuck low, the master should send nine * clock pulses.
++ * The I2C slave device that held the bus low should release it
++ * sometime within * those nine clocks. Due to this erratum,
++ * the I2C controller cannot generate nine clock pulses.
++ */
++static int i2c_imx_recovery_for_layerscape(struct imx_i2c_struct *i2c_imx)
++{
++ u32 pmuxcr = 0;
++ int ret;
++ unsigned int i, temp;
++
++ /* configure IICx_SCL/GPIO pin as a GPIO */
++ if (i2c_imx->need_set_pmuxcr == 1) {
++ pmuxcr = ioread32be(i2c_imx->pmuxcr_addr);
++ if (i2c_imx->pmuxcr_endian == BIG_ENDIAN)
++ iowrite32be(i2c_imx->pmuxcr_set|pmuxcr,
++ i2c_imx->pmuxcr_addr);
++ else
++ iowrite32(i2c_imx->pmuxcr_set|pmuxcr,
++ i2c_imx->pmuxcr_addr);
++ }
++
++ ret = gpio_request(i2c_imx->gpio, i2c_imx->adapter.name);
++ if (ret) {
++ dev_err(&i2c_imx->adapter.dev,
++ "can't get gpio: %d\n", ret);
++ return ret;
++ }
++
++ /* Configure GPIO pin as an output and open drain. */
++ gpio_direction_output(i2c_imx->gpio, 1);
++ udelay(10);
++
++ /* Write data to generate 9 pulses */
++ for (i = 0; i < 9; i++) {
++ gpio_set_value(i2c_imx->gpio, 1);
++ udelay(10);
++ gpio_set_value(i2c_imx->gpio, 0);
++ udelay(10);
++ }
++ /* ensure that the last level sent is always high */
++ gpio_set_value(i2c_imx->gpio, 1);
++
++ /*
++ * Set I2Cx_IBCR = 0h00 to generate a STOP and then
++ * set I2Cx_IBCR = 0h80 to reset
++ */
++ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
++ temp &= ~(I2CR_MSTA | I2CR_MTX);
++ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
++
++ /* Restore the saved value of the register SCFG_RCWPMUXCR0 */
++ if (i2c_imx->need_set_pmuxcr == 1) {
++ if (i2c_imx->pmuxcr_endian == BIG_ENDIAN)
++ iowrite32be(pmuxcr, i2c_imx->pmuxcr_addr);
++ else
++ iowrite32(pmuxcr, i2c_imx->pmuxcr_addr);
++ }
++ /*
++ * Set I2C_IBSR[IBAL] to clear the IBAL bit if-
++ * I2C_IBSR[IBAL] = 1
++ */
++ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
++ if (temp & I2SR_IAL) {
++ temp &= ~I2SR_IAL;
++ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
++ }
++ return 0;
++}
++
+ static int i2c_imx_xfer(struct i2c_adapter *adapter,
+ struct i2c_msg *msgs, int num)
+ {
+@@ -889,6 +1020,19 @@ static int i2c_imx_xfer(struct i2c_adapt
dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
+ * before switching to master mode and attempting a Start cycle
+ */
+ result = i2c_imx_bus_busy(i2c_imx, 0);
-+ if (result)
-+ goto out;
++ if (result) {
++ /* timeout */
++ if ((result == -ETIMEDOUT) && (i2c_imx->layerscape_bus_recover == 1))
++ i2c_imx_recovery_for_layerscape(i2c_imx);
++ else
++ goto out;
++ }
+
result = pm_runtime_get_sync(i2c_imx->adapter.dev.parent);
if (result < 0)
goto out;
-@@ -1100,7 +1108,7 @@ static int i2c_imx_probe(struct platform_device *pdev)
+@@ -1031,6 +1175,50 @@ static int i2c_imx_init_recovery_info(st
+ return 0;
+ }
+
++/*
++ * switch SCL and SDA to their GPIO function and do some bitbanging
++ * for bus recovery.
++ * There are platforms such as Layerscape that don't support pinctrl, so add
++ * workaround for layerscape, it has no effect for other platforms.
++ */
++static int i2c_imx_init_recovery_for_layerscape(
++ struct imx_i2c_struct *i2c_imx,
++ struct platform_device *pdev)
++{
++ const struct of_device_id *of_id;
++ struct device_node *np = pdev->dev.of_node;
++ struct pinmux_cfg *pinmux_cfg;
++ struct device_node *scfg_node;
++ void __iomem *scfg_base = NULL;
++
++ i2c_imx->gpio = of_get_named_gpio(np, "fsl-scl-gpio", 0);
++ if (!gpio_is_valid(i2c_imx->gpio)) {
++ dev_info(&pdev->dev, "fsl-scl-gpio not found\n");
++ return 0;
++ }
++ pinmux_cfg = devm_kzalloc(&pdev->dev, sizeof(*pinmux_cfg), GFP_KERNEL);
++ if (!pinmux_cfg)
++ return -ENOMEM;
++
++ i2c_imx->need_set_pmuxcr = 0;
++ of_id = of_match_node(pinmux_of_match, np);
++ if (of_id) {
++ pinmux_cfg = (struct pinmux_cfg *)of_id->data;
++ i2c_imx->pmuxcr_endian = pinmux_cfg->endian;
++ i2c_imx->pmuxcr_set = pinmux_cfg->pmuxcr_set_bit;
++ scfg_node = of_find_matching_node(NULL, scfg_device_ids);
++ if (scfg_node) {
++ scfg_base = of_iomap(scfg_node, 0);
++ if (scfg_base) {
++ i2c_imx->pmuxcr_addr = scfg_base + pinmux_cfg->pmuxcr_offset;
++ i2c_imx->need_set_pmuxcr = 1;
++ }
++ }
++ }
++ i2c_imx->layerscape_bus_recover = 1;
++ return 0;
++}
++
+ static u32 i2c_imx_func(struct i2c_adapter *adapter)
+ {
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
+@@ -1086,6 +1274,11 @@ static int i2c_imx_probe(struct platform
+ i2c_imx->adapter.dev.of_node = pdev->dev.of_node;
+ i2c_imx->base = base;
+
++ /* Init optional bus recovery for layerscape */
++ ret = i2c_imx_init_recovery_for_layerscape(i2c_imx, pdev);
++ if (ret)
++ return ret;
++
+ /* Get I2C clock */
+ i2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(i2c_imx->clk)) {
+@@ -1100,7 +1293,7 @@ static int i2c_imx_probe(struct platform
}
/* Request IRQ */
pdev->name, i2c_imx);
if (ret) {
dev_err(&pdev->dev, "can't claim irq %d\n", irq);
-diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
-index 9c4ac26c..3c27ab84 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -74,6 +74,7 @@ struct pca954x {
};
/* Provide specs for the PCA954x types we know about */
-@@ -196,6 +197,13 @@ static int pca954x_deselect_mux(struct i2c_mux_core *muxc, u32 chan)
+@@ -196,6 +197,13 @@ static int pca954x_deselect_mux(struct i
if (!(data->deselect & (1 << chan)))
return 0;
/* Deselect active channel */
data->last_chan = 0;
return pca954x_reg_write(muxc->parent, client, data->last_chan);
-@@ -228,6 +236,28 @@ static int pca954x_probe(struct i2c_client *client,
+@@ -228,6 +236,28 @@ static int pca954x_probe(struct i2c_clie
return -ENOMEM;
data = i2c_mux_priv(muxc);
i2c_set_clientdata(client, muxc);
data->client = client;
-@@ -240,11 +270,16 @@ static int pca954x_probe(struct i2c_client *client,
+@@ -240,11 +270,16 @@ static int pca954x_probe(struct i2c_clie
* that the mux is in fact present. This also
* initializes the mux to disconnected state.
*/
match = of_match_device(of_match_ptr(pca954x_of_match), &client->dev);
if (match)
data->chip = of_device_get_match_data(&client->dev);
-@@ -252,6 +287,7 @@ static int pca954x_probe(struct i2c_client *client,
+@@ -252,6 +287,7 @@ static int pca954x_probe(struct i2c_clie
data->chip = &chips[id->driver_data];
data->last_chan = 0; /* force the first selection */
idle_disconnect_dt = of_node &&
of_property_read_bool(of_node, "i2c-mux-idle-disconnect");
-@@ -312,6 +348,13 @@ static int pca954x_resume(struct device *dev)
+@@ -312,6 +348,13 @@ static int pca954x_resume(struct device
struct i2c_mux_core *muxc = i2c_get_clientdata(client);
struct pca954x *data = i2c_mux_priv(muxc);
data->last_chan = 0;
return i2c_smbus_write_byte(client, 0);
}
---
-2.14.1
-
projects / openwrt / openwrt.git / blobdiff