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-rw-r--r--drivers/i2c/muxes/Kconfig11
-rw-r--r--drivers/i2c/muxes/Makefile1
-rw-r--r--drivers/i2c/muxes/i2c-arb-gpio-challenge.c3
-rw-r--r--drivers/i2c/muxes/i2c-mux-gpio.c1
-rw-r--r--drivers/i2c/muxes/i2c-mux-pca9541.c1
-rw-r--r--drivers/i2c/muxes/i2c-mux-pca954x.c1
-rw-r--r--drivers/i2c/muxes/i2c-mux-pinctrl.c1
-rw-r--r--drivers/i2c/muxes/i2c-mux-reg.c290
8 files changed, 306 insertions, 3 deletions
diff --git a/drivers/i2c/muxes/Kconfig b/drivers/i2c/muxes/Kconfig
index fdd0769c8..f06b0e246 100644
--- a/drivers/i2c/muxes/Kconfig
+++ b/drivers/i2c/muxes/Kconfig
@@ -61,4 +61,15 @@ config I2C_MUX_PINCTRL
This driver can also be built as a module. If so, the module will be
called pinctrl-i2cmux.
+config I2C_MUX_REG
+ tristate "Register-based I2C multiplexer"
+ help
+ If you say yes to this option, support will be included for a
+ register based I2C multiplexer. This driver provides access to
+ I2C busses connected through a MUX, which is controlled
+ by a single register.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-mux-reg.
+
endmenu
diff --git a/drivers/i2c/muxes/Makefile b/drivers/i2c/muxes/Makefile
index 465778b5d..e89799b76 100644
--- a/drivers/i2c/muxes/Makefile
+++ b/drivers/i2c/muxes/Makefile
@@ -7,5 +7,6 @@ obj-$(CONFIG_I2C_MUX_GPIO) += i2c-mux-gpio.o
obj-$(CONFIG_I2C_MUX_PCA9541) += i2c-mux-pca9541.o
obj-$(CONFIG_I2C_MUX_PCA954x) += i2c-mux-pca954x.o
obj-$(CONFIG_I2C_MUX_PINCTRL) += i2c-mux-pinctrl.o
+obj-$(CONFIG_I2C_MUX_REG) += i2c-mux-reg.o
ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG
diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
index 5cf1b60b6..402e3a6c6 100644
--- a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
+++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
@@ -196,7 +196,8 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
dev_err(dev, "Cannot parse i2c-parent\n");
return -EINVAL;
}
- arb->parent = of_find_i2c_adapter_by_node(parent_np);
+ arb->parent = of_get_i2c_adapter_by_node(parent_np);
+ of_node_put(parent_np);
if (!arb->parent) {
dev_err(dev, "Cannot find parent bus\n");
return -EPROBE_DEFER;
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index 70db99264..b8e11c16d 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -76,6 +76,7 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux,
return -ENODEV;
}
adapter = of_find_i2c_adapter_by_node(adapter_np);
+ of_node_put(adapter_np);
if (!adapter)
return -EPROBE_DEFER;
diff --git a/drivers/i2c/muxes/i2c-mux-pca9541.c b/drivers/i2c/muxes/i2c-mux-pca9541.c
index 0c8d4d2cb..d0ba424ad 100644
--- a/drivers/i2c/muxes/i2c-mux-pca9541.c
+++ b/drivers/i2c/muxes/i2c-mux-pca9541.c
@@ -386,7 +386,6 @@ static int pca9541_remove(struct i2c_client *client)
static struct i2c_driver pca9541_driver = {
.driver = {
.name = "pca9541",
- .owner = THIS_MODULE,
},
.probe = pca9541_probe,
.remove = pca9541_remove,
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index ea4aa9dfc..acfcef3d4 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -300,7 +300,6 @@ static struct i2c_driver pca954x_driver = {
.driver = {
.name = "pca954x",
.pm = &pca954x_pm,
- .owner = THIS_MODULE,
},
.probe = pca954x_probe,
.remove = pca954x_remove,
diff --git a/drivers/i2c/muxes/i2c-mux-pinctrl.c b/drivers/i2c/muxes/i2c-mux-pinctrl.c
index b48378c4b..b5a982ba8 100644
--- a/drivers/i2c/muxes/i2c-mux-pinctrl.c
+++ b/drivers/i2c/muxes/i2c-mux-pinctrl.c
@@ -111,6 +111,7 @@ static int i2c_mux_pinctrl_parse_dt(struct i2c_mux_pinctrl *mux,
return -ENODEV;
}
adapter = of_find_i2c_adapter_by_node(adapter_np);
+ of_node_put(adapter_np);
if (!adapter) {
dev_err(mux->dev, "Cannot find parent bus\n");
return -EPROBE_DEFER;
diff --git a/drivers/i2c/muxes/i2c-mux-reg.c b/drivers/i2c/muxes/i2c-mux-reg.c
new file mode 100644
index 000000000..5fbd5bd08
--- /dev/null
+++ b/drivers/i2c/muxes/i2c-mux-reg.c
@@ -0,0 +1,290 @@
+/*
+ * I2C multiplexer using a single register
+ *
+ * Copyright 2015 Freescale Semiconductor
+ * York Sun <yorksun@freescale.com>
+ *
+ * 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.
+ */
+
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/platform_data/i2c-mux-reg.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+struct regmux {
+ struct i2c_adapter *parent;
+ struct i2c_adapter **adap; /* child busses */
+ struct i2c_mux_reg_platform_data data;
+};
+
+static int i2c_mux_reg_set(const struct regmux *mux, unsigned int chan_id)
+{
+ if (!mux->data.reg)
+ return -EINVAL;
+
+ /*
+ * Write to the register, followed by a read to ensure the write is
+ * completed on a "posted" bus, for example PCI or write buffers.
+ * The endianness of reading doesn't matter and the return data
+ * is not used.
+ */
+ switch (mux->data.reg_size) {
+ case 4:
+ if (mux->data.little_endian)
+ iowrite32(chan_id, mux->data.reg);
+ else
+ iowrite32be(chan_id, mux->data.reg);
+ if (!mux->data.write_only)
+ ioread32(mux->data.reg);
+ break;
+ case 2:
+ if (mux->data.little_endian)
+ iowrite16(chan_id, mux->data.reg);
+ else
+ iowrite16be(chan_id, mux->data.reg);
+ if (!mux->data.write_only)
+ ioread16(mux->data.reg);
+ break;
+ case 1:
+ iowrite8(chan_id, mux->data.reg);
+ if (!mux->data.write_only)
+ ioread8(mux->data.reg);
+ break;
+ }
+
+ return 0;
+}
+
+static int i2c_mux_reg_select(struct i2c_adapter *adap, void *data,
+ unsigned int chan)
+{
+ struct regmux *mux = data;
+
+ return i2c_mux_reg_set(mux, chan);
+}
+
+static int i2c_mux_reg_deselect(struct i2c_adapter *adap, void *data,
+ unsigned int chan)
+{
+ struct regmux *mux = data;
+
+ if (mux->data.idle_in_use)
+ return i2c_mux_reg_set(mux, mux->data.idle);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static int i2c_mux_reg_probe_dt(struct regmux *mux,
+ struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct device_node *adapter_np, *child;
+ struct i2c_adapter *adapter;
+ struct resource res;
+ unsigned *values;
+ int i = 0;
+
+ if (!np)
+ return -ENODEV;
+
+ adapter_np = of_parse_phandle(np, "i2c-parent", 0);
+ if (!adapter_np) {
+ dev_err(&pdev->dev, "Cannot parse i2c-parent\n");
+ return -ENODEV;
+ }
+ adapter = of_find_i2c_adapter_by_node(adapter_np);
+ of_node_put(adapter_np);
+ if (!adapter)
+ return -EPROBE_DEFER;
+
+ mux->parent = adapter;
+ mux->data.parent = i2c_adapter_id(adapter);
+ put_device(&adapter->dev);
+
+ mux->data.n_values = of_get_child_count(np);
+ if (of_find_property(np, "little-endian", NULL)) {
+ mux->data.little_endian = true;
+ } else if (of_find_property(np, "big-endian", NULL)) {
+ mux->data.little_endian = false;
+ } else {
+#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : \
+ defined(__LITTLE_ENDIAN)
+ mux->data.little_endian = true;
+#elif defined(__BYTE_ORDER) ? __BYTE_ORDER == __BIG_ENDIAN : \
+ defined(__BIG_ENDIAN)
+ mux->data.little_endian = false;
+#else
+#error Endianness not defined?
+#endif
+ }
+ if (of_find_property(np, "write-only", NULL))
+ mux->data.write_only = true;
+ else
+ mux->data.write_only = false;
+
+ values = devm_kzalloc(&pdev->dev,
+ sizeof(*mux->data.values) * mux->data.n_values,
+ GFP_KERNEL);
+ if (!values) {
+ dev_err(&pdev->dev, "Cannot allocate values array");
+ return -ENOMEM;
+ }
+
+ for_each_child_of_node(np, child) {
+ of_property_read_u32(child, "reg", values + i);
+ i++;
+ }
+ mux->data.values = values;
+
+ if (!of_property_read_u32(np, "idle-state", &mux->data.idle))
+ mux->data.idle_in_use = true;
+
+ /* map address from "reg" if exists */
+ if (of_address_to_resource(np, 0, &res)) {
+ mux->data.reg_size = resource_size(&res);
+ mux->data.reg = devm_ioremap_resource(&pdev->dev, &res);
+ if (IS_ERR(mux->data.reg))
+ return PTR_ERR(mux->data.reg);
+ }
+
+ return 0;
+}
+#else
+static int i2c_mux_reg_probe_dt(struct regmux *mux,
+ struct platform_device *pdev)
+{
+ return 0;
+}
+#endif
+
+static int i2c_mux_reg_probe(struct platform_device *pdev)
+{
+ struct regmux *mux;
+ struct i2c_adapter *parent;
+ struct resource *res;
+ int (*deselect)(struct i2c_adapter *, void *, u32);
+ unsigned int class;
+ int i, ret, nr;
+
+ mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL);
+ if (!mux)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, mux);
+
+ if (dev_get_platdata(&pdev->dev)) {
+ memcpy(&mux->data, dev_get_platdata(&pdev->dev),
+ sizeof(mux->data));
+
+ parent = i2c_get_adapter(mux->data.parent);
+ if (!parent)
+ return -EPROBE_DEFER;
+
+ mux->parent = parent;
+ } else {
+ ret = i2c_mux_reg_probe_dt(mux, pdev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Error parsing device tree");
+ return ret;
+ }
+ }
+
+ if (!mux->data.reg) {
+ dev_info(&pdev->dev,
+ "Register not set, using platform resource\n");
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ mux->data.reg_size = resource_size(res);
+ mux->data.reg = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(mux->data.reg))
+ return PTR_ERR(mux->data.reg);
+ }
+
+ if (mux->data.reg_size != 4 && mux->data.reg_size != 2 &&
+ mux->data.reg_size != 1) {
+ dev_err(&pdev->dev, "Invalid register size\n");
+ return -EINVAL;
+ }
+
+ mux->adap = devm_kzalloc(&pdev->dev,
+ sizeof(*mux->adap) * mux->data.n_values,
+ GFP_KERNEL);
+ if (!mux->adap) {
+ dev_err(&pdev->dev, "Cannot allocate i2c_adapter structure");
+ return -ENOMEM;
+ }
+
+ if (mux->data.idle_in_use)
+ deselect = i2c_mux_reg_deselect;
+ else
+ deselect = NULL;
+
+ for (i = 0; i < mux->data.n_values; i++) {
+ nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
+ class = mux->data.classes ? mux->data.classes[i] : 0;
+
+ mux->adap[i] = i2c_add_mux_adapter(mux->parent, &pdev->dev, mux,
+ nr, mux->data.values[i],
+ class, i2c_mux_reg_select,
+ deselect);
+ if (!mux->adap[i]) {
+ ret = -ENODEV;
+ dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
+ goto add_adapter_failed;
+ }
+ }
+
+ dev_dbg(&pdev->dev, "%d port mux on %s adapter\n",
+ mux->data.n_values, mux->parent->name);
+
+ return 0;
+
+add_adapter_failed:
+ for (; i > 0; i--)
+ i2c_del_mux_adapter(mux->adap[i - 1]);
+
+ return ret;
+}
+
+static int i2c_mux_reg_remove(struct platform_device *pdev)
+{
+ struct regmux *mux = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < mux->data.n_values; i++)
+ i2c_del_mux_adapter(mux->adap[i]);
+
+ i2c_put_adapter(mux->parent);
+
+ return 0;
+}
+
+static const struct of_device_id i2c_mux_reg_of_match[] = {
+ { .compatible = "i2c-mux-reg", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, i2c_mux_reg_of_match);
+
+static struct platform_driver i2c_mux_reg_driver = {
+ .probe = i2c_mux_reg_probe,
+ .remove = i2c_mux_reg_remove,
+ .driver = {
+ .name = "i2c-mux-reg",
+ },
+};
+
+module_platform_driver(i2c_mux_reg_driver);
+
+MODULE_DESCRIPTION("Register-based I2C multiplexer driver");
+MODULE_AUTHOR("York Sun <yorksun@freescale.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:i2c-mux-reg");
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-04 16:51:25 +0000