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authorLinus Torvalds <torvalds@linux-foundation.org>2016-12-15 12:56:35 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-15 12:56:35 -0800
commit8600b697cd4787ac3ce053d48ca7301836fd0c55 (patch)
treeba0771e53ffb66b2c077b54f620d9bb78b43ba79 /drivers/i2c/muxes
parent0ab7b12c49b6fbf2d4d0381374b82935f949be5f (diff)
parent6eb89ef029fe22aee518a9dc75b9ee5d6ef9b3fe (diff)
downloadlinux-8600b697cd4787ac3ce053d48ca7301836fd0c55.tar.gz
Merge branch 'i2c/for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:

 - the first series of making i2c_device_id optional instead of
   mandatory (in favor of alternatives like of_device_id).

   This involves adding a new probe callback (probe_new) which removes
   some peculiarities I2C had for a long time now. The new probe is
   matching the other subsystems now and the old one will be removed
   once all users are converted. It is expected to take a while but
   there is ongoing interest in that.

 - SMBus Host Notify introduced 4.9 got refactored. They are now using
   interrupts instead of the alert callback which solves multiple
   issues.

 - new drivers for iMX LowPower I2C, Mellanox CPLD and its I2C mux

 - significant refactoring for bcm2835 driver

 - the usual set of driver updates and improvements

* 'i2c/for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (46 commits)
  i2c: fsl-lpi2c: read lpi2c fifo size in probe()
  i2c: octeon: thunderx: Remove double-check after interrupt
  i2c: octeon: thunderx: TWSI software reset in recovery
  i2c: cadence: Allow Cadence I2C to be selected for Cadence Xtensa CPUs
  i2c: sh_mobile: Add per-Generation fallback bindings
  i2c: rcar: Add per-Generation fallback bindings
  i2c: imx-lpi2c: add low power i2c bus driver
  dt-bindings: i2c: imx-lpi2c: add devicetree bindings
  i2c: designware-pcidrv: Add 10bit address feature to medfield/merrifield
  i2c: pxa: Add support for the I2C units found in Armada 3700
  i2c: pxa: Add definition of fast and high speed modes via the regs layout
  dt-bindings: i2c: pxa: Update the documentation for the Armada 3700
  i2c: qup: support SMBus block read
  i2c: qup: add ACPI support
  i2c: designware: Consolidate default functionality bits
  i2c: i2c-mux-gpio: update mux with gpiod_set_array_value_cansleep
  i2c: mux: pca954x: Add ACPI support for pca954x
  i2c: use an IRQ to report Host Notify events, not alert
  i2c: i801: remove SMBNTFDDAT reads as they always seem to return 0
  i2c: i801: use the BIT() macro for FEATURES_* also
  ...
Diffstat (limited to 'drivers/i2c/muxes')
-rw-r--r--drivers/i2c/muxes/Kconfig11
-rw-r--r--drivers/i2c/muxes/Makefile1
-rw-r--r--drivers/i2c/muxes/i2c-mux-gpio.c18
-rw-r--r--drivers/i2c/muxes/i2c-mux-mlxcpld.c220
-rw-r--r--drivers/i2c/muxes/i2c-mux-pca954x.c28
5 files changed, 273 insertions, 5 deletions
diff --git a/drivers/i2c/muxes/Kconfig b/drivers/i2c/muxes/Kconfig
index 96de9ce5669b..10b3d17ae3ea 100644
--- a/drivers/i2c/muxes/Kconfig
+++ b/drivers/i2c/muxes/Kconfig
@@ -82,4 +82,15 @@ config I2C_DEMUX_PINCTRL
 	  demultiplexer that uses the pinctrl subsystem. This is useful if you
 	  want to change the I2C master at run-time depending on features.
 
+config I2C_MUX_MLXCPLD
+        tristate "Mellanox CPLD based I2C multiplexer"
+        help
+          If you say yes to this option, support will be included for a
+          CPLD based I2C multiplexer. This driver provides access to
+          I2C busses connected through a MUX, which is controlled
+          by a CPLD register.
+
+          This driver can also be built as a module.  If so, the module
+          will be called i2c-mux-mlxcpld.
+
 endmenu
diff --git a/drivers/i2c/muxes/Makefile b/drivers/i2c/muxes/Makefile
index 7c267c29b191..9948fa45037f 100644
--- a/drivers/i2c/muxes/Makefile
+++ b/drivers/i2c/muxes/Makefile
@@ -6,6 +6,7 @@ obj-$(CONFIG_I2C_ARB_GPIO_CHALLENGE)	+= i2c-arb-gpio-challenge.o
 obj-$(CONFIG_I2C_DEMUX_PINCTRL)		+= i2c-demux-pinctrl.o
 
 obj-$(CONFIG_I2C_MUX_GPIO)	+= i2c-mux-gpio.o
+obj-$(CONFIG_I2C_MUX_MLXCPLD)	+= i2c-mux-mlxcpld.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
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index e5cf26eefa97..655684d621a4 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -21,6 +21,8 @@
 struct gpiomux {
 	struct i2c_mux_gpio_platform_data data;
 	unsigned gpio_base;
+	struct gpio_desc **gpios;
+	int *values;
 };
 
 static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val)
@@ -28,8 +30,10 @@ static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val)
 	int i;
 
 	for (i = 0; i < mux->data.n_gpios; i++)
-		gpio_set_value_cansleep(mux->gpio_base + mux->data.gpios[i],
-					val & (1 << i));
+		mux->values[i] = (val >> i) & 1;
+
+	gpiod_set_array_value_cansleep(mux->data.n_gpios,
+				       mux->gpios, mux->values);
 }
 
 static int i2c_mux_gpio_select(struct i2c_mux_core *muxc, u32 chan)
@@ -176,12 +180,16 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
 	if (!parent)
 		return -EPROBE_DEFER;
 
-	muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values, 0, 0,
+	muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values,
+			     mux->data.n_gpios * sizeof(*mux->gpios) +
+			     mux->data.n_gpios * sizeof(*mux->values), 0,
 			     i2c_mux_gpio_select, NULL);
 	if (!muxc) {
 		ret = -ENOMEM;
 		goto alloc_failed;
 	}
+	mux->gpios = muxc->priv;
+	mux->values = (int *)(mux->gpios + mux->data.n_gpios);
 	muxc->priv = mux;
 
 	platform_set_drvdata(pdev, muxc);
@@ -219,10 +227,12 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
 			goto err_request_gpio;
 		}
 
+		gpio_desc = gpio_to_desc(gpio_base + mux->data.gpios[i]);
+		mux->gpios[i] = gpio_desc;
+
 		if (!muxc->mux_locked)
 			continue;
 
-		gpio_desc = gpio_to_desc(gpio_base + mux->data.gpios[i]);
 		gpio_dev = &gpio_desc->gdev->dev;
 		muxc->mux_locked = i2c_root_adapter(gpio_dev) == root;
 	}
diff --git a/drivers/i2c/muxes/i2c-mux-mlxcpld.c b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
new file mode 100644
index 000000000000..3ab654bbfab5
--- /dev/null
+++ b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
@@ -0,0 +1,220 @@
+/*
+ * drivers/i2c/muxes/i2c-mux-mlxcpld.c
+ * Copyright (c) 2016 Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2016 Michael Shych <michaels@mellanox.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/version.h>
+#include <linux/i2c/mlxcpld.h>
+
+#define CPLD_MUX_MAX_NCHANS	8
+
+/* mlxcpld_mux - mux control structure:
+ * @last_chan - last register value
+ * @client - I2C device client
+ */
+struct mlxcpld_mux {
+	u8 last_chan;
+	struct i2c_client *client;
+};
+
+/* MUX logic description.
+ * Driver can support different mux control logic, according to CPLD
+ * implementation.
+ *
+ * Connectivity schema.
+ *
+ * i2c-mlxcpld                                 Digital               Analog
+ * driver
+ * *--------*                                 * -> mux1 (virt bus2) -> mux -> |
+ * | I2CLPC | i2c physical                    * -> mux2 (virt bus3) -> mux -> |
+ * | bridge | bus 1                 *---------*                               |
+ * | logic  |---------------------> * mux reg *                               |
+ * | in CPLD|                       *---------*                               |
+ * *--------*   i2c-mux-mlxpcld          ^    * -> muxn (virt busn) -> mux -> |
+ *     |        driver                   |                                    |
+ *     |        *---------------*        |                              Devices
+ *     |        * CPLD (i2c bus)* select |
+ *     |        * registers for *--------*
+ *     |        * mux selection * deselect
+ *     |        *---------------*
+ *     |                 |
+ * <-------->     <----------->
+ * i2c cntrl      Board cntrl reg
+ * reg space      space (mux select,
+ *                IO, LED, WD, info)
+ *
+ */
+
+static const struct i2c_device_id mlxcpld_mux_id[] = {
+	{ "mlxcpld_mux_module", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, mlxcpld_mux_id);
+
+/* Write to mux register. Don't use i2c_transfer() and i2c_smbus_xfer()
+ * for this as they will try to lock adapter a second time.
+ */
+static int mlxcpld_mux_reg_write(struct i2c_adapter *adap,
+				 struct i2c_client *client, u8 val)
+{
+	struct mlxcpld_mux_plat_data *pdata = dev_get_platdata(&client->dev);
+
+	if (adap->algo->master_xfer) {
+		struct i2c_msg msg;
+		u8 msgbuf[] = {pdata->sel_reg_addr, val};
+
+		msg.addr = client->addr;
+		msg.flags = 0;
+		msg.len = 2;
+		msg.buf = msgbuf;
+		return __i2c_transfer(adap, &msg, 1);
+	} else if (adap->algo->smbus_xfer) {
+		union i2c_smbus_data data;
+
+		data.byte = val;
+		return adap->algo->smbus_xfer(adap, client->addr,
+					      client->flags, I2C_SMBUS_WRITE,
+					      pdata->sel_reg_addr,
+					      I2C_SMBUS_BYTE_DATA, &data);
+	} else
+		return -ENODEV;
+}
+
+static int mlxcpld_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
+{
+	struct mlxcpld_mux *data = i2c_mux_priv(muxc);
+	struct i2c_client *client = data->client;
+	u8 regval = chan + 1;
+	int err = 0;
+
+	/* Only select the channel if its different from the last channel */
+	if (data->last_chan != regval) {
+		err = mlxcpld_mux_reg_write(muxc->parent, client, regval);
+		if (err)
+			data->last_chan = 0;
+		else
+			data->last_chan = regval;
+	}
+
+	return err;
+}
+
+static int mlxcpld_mux_deselect(struct i2c_mux_core *muxc, u32 chan)
+{
+	struct mlxcpld_mux *data = i2c_mux_priv(muxc);
+	struct i2c_client *client = data->client;
+
+	/* Deselect active channel */
+	data->last_chan = 0;
+
+	return mlxcpld_mux_reg_write(muxc->parent, client, data->last_chan);
+}
+
+/* Probe/reomove functions */
+static int mlxcpld_mux_probe(struct i2c_client *client,
+			     const struct i2c_device_id *id)
+{
+	struct i2c_adapter *adap = to_i2c_adapter(client->dev.parent);
+	struct mlxcpld_mux_plat_data *pdata = dev_get_platdata(&client->dev);
+	struct i2c_mux_core *muxc;
+	int num, force;
+	struct mlxcpld_mux *data;
+	int err;
+
+	if (!pdata)
+		return -EINVAL;
+
+	if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
+		return -ENODEV;
+
+	muxc = i2c_mux_alloc(adap, &client->dev, CPLD_MUX_MAX_NCHANS,
+			     sizeof(*data), 0, mlxcpld_mux_select_chan,
+			     mlxcpld_mux_deselect);
+	if (!muxc)
+		return -ENOMEM;
+
+	data = i2c_mux_priv(muxc);
+	i2c_set_clientdata(client, muxc);
+	data->client = client;
+	data->last_chan = 0; /* force the first selection */
+
+	/* Create an adapter for each channel. */
+	for (num = 0; num < CPLD_MUX_MAX_NCHANS; num++) {
+		if (num >= pdata->num_adaps)
+			/* discard unconfigured channels */
+			break;
+
+		force = pdata->adap_ids[num];
+
+		err = i2c_mux_add_adapter(muxc, force, num, 0);
+		if (err)
+			goto virt_reg_failed;
+	}
+
+	return 0;
+
+virt_reg_failed:
+	i2c_mux_del_adapters(muxc);
+	return err;
+}
+
+static int mlxcpld_mux_remove(struct i2c_client *client)
+{
+	struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+
+	i2c_mux_del_adapters(muxc);
+	return 0;
+}
+
+static struct i2c_driver mlxcpld_mux_driver = {
+	.driver		= {
+		.name	= "mlxcpld-mux",
+	},
+	.probe		= mlxcpld_mux_probe,
+	.remove		= mlxcpld_mux_remove,
+	.id_table	= mlxcpld_mux_id,
+};
+
+module_i2c_driver(mlxcpld_mux_driver);
+
+MODULE_AUTHOR("Michael Shych (michaels@mellanox.com)");
+MODULE_DESCRIPTION("Mellanox I2C-CPLD-MUX driver");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS("platform:i2c-mux-mlxcpld");
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 8bc3d36d2837..9a348ee4dc14 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -35,6 +35,7 @@
  * warranty of any kind, whether express or implied.
  */
 
+#include <linux/acpi.h>
 #include <linux/device.h>
 #include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
@@ -120,6 +121,21 @@ static const struct i2c_device_id pca954x_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, pca954x_id);
 
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id pca954x_acpi_ids[] = {
+	{ .id = "PCA9540", .driver_data = pca_9540 },
+	{ .id = "PCA9542", .driver_data = pca_9540 },
+	{ .id = "PCA9543", .driver_data = pca_9543 },
+	{ .id = "PCA9544", .driver_data = pca_9544 },
+	{ .id = "PCA9545", .driver_data = pca_9545 },
+	{ .id = "PCA9546", .driver_data = pca_9545 },
+	{ .id = "PCA9547", .driver_data = pca_9547 },
+	{ .id = "PCA9548", .driver_data = pca_9548 },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, pca954x_acpi_ids);
+#endif
+
 #ifdef CONFIG_OF
 static const struct of_device_id pca954x_of_match[] = {
 	{ .compatible = "nxp,pca9540", .data = &chips[pca_9540] },
@@ -245,8 +261,17 @@ static int pca954x_probe(struct i2c_client *client,
 	match = of_match_device(of_match_ptr(pca954x_of_match), &client->dev);
 	if (match)
 		data->chip = of_device_get_match_data(&client->dev);
-	else
+	else if (id)
 		data->chip = &chips[id->driver_data];
+	else {
+		const struct acpi_device_id *acpi_id;
+
+		acpi_id = acpi_match_device(ACPI_PTR(pca954x_acpi_ids),
+						&client->dev);
+		if (!acpi_id)
+			return -ENODEV;
+		data->chip = &chips[acpi_id->driver_data];
+	}
 
 	data->last_chan = 0;		   /* force the first selection */
 
@@ -321,6 +346,7 @@ static struct i2c_driver pca954x_driver = {
 		.name	= "pca954x",
 		.pm	= &pca954x_pm,
 		.of_match_table = of_match_ptr(pca954x_of_match),
+		.acpi_match_table = ACPI_PTR(pca954x_acpi_ids),
 	},
 	.probe		= pca954x_probe,
 	.remove		= pca954x_remove,