@@ -848,6 +848,18 @@ config I2C_RCAR
comment "External I2C/SMBus adapter drivers"
+config I2C_CYUSBS23X
+ tristate "CYUSBS23x I2C adapter"
+ depends on MFD_CYUSBS23X && USB
+ help
+ Say yes if you would like to access Cypress CYUSBS23x I2C device.
+
+ This driver enables the I2C interface of CYUSBS23x USB Serial Bridge
+ controller.
+
+ This driver can also be built as a module. If so, the module will be
+ called i2c-cyusbs23x.
+
config I2C_DIOLAN_U2C
tristate "Diolan U2C-12 USB adapter"
depends on USB
@@ -84,6 +84,7 @@ obj-$(CONFIG_I2C_XLR) += i2c-xlr.o
obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o
# External I2C/SMBus adapter drivers
+obj-$(CONFIG_I2C_CYUSBS23X) += i2c-cyusbs23x.o
obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o
obj-$(CONFIG_I2C_PARPORT) += i2c-parport.o
obj-$(CONFIG_I2C_PARPORT_LIGHT) += i2c-parport-light.o
new file mode 100644
@@ -0,0 +1,584 @@
+/*
+ * I2C subdriver for Cypress CYUSBS234 USB-Serial Bridge controller.
+ * Details about the device can be found at:
+ * http://www.cypress.com/?rID=84126
+ *
+ * Copyright (c) 2014 Cypress Semiconductor Corporation.
+ *
+ * Author:
+ * Rajaram Regupathy <rera@cypress.com>
+ *
+ * Additional contributors include:
+ * Muthu Mani <muth@cypress.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+
+/*
+ * It exposes sysfs entries under the i2c adapter for getting the i2c transfer
+ * status, reset i2c read/write module, get/set nak and stop bits.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+
+#include <linux/usb.h>
+#include <linux/i2c.h>
+
+#include <linux/mfd/cyusbs23x.h>
+
+enum cy_i2c_io_mode {
+ CY_I2C_MODE_READ = 0,
+ CY_I2C_MODE_WRITE = 1
+};
+
+#define CY_I2C_XFER_STATUS_LEN 3
+
+struct cyusbs_i2c_config {
+ /* Frequency of operation. Only valid values are 100KHz and 400KHz */
+ u32 frequency;
+ u8 slave_addr; /* Slave address to be used when in slave mode */
+ u8 is_msb_first; /* Whether to transmit MSB first */
+ /*
+ * Whether block is configured as a master:
+ * 1 - The block functions as I2C master;
+ * 0 - The block functions as I2C slave
+ */
+ u8 is_master;
+ u8 s_ignore; /* Ignore general call in slave mode */
+ /* Whether to stretch clock in case of no FIFO availability */
+ u8 clock_stretch;
+ /* Whether to loop back TX data to RX. Valid only for debug purposes */
+ u8 is_loopback;
+ u8 reserved[6]; /* Reserved for future use */
+} __packed;
+
+struct cyusbs_i2c {
+ struct i2c_adapter i2c_adapter;
+ struct cyusbs_i2c_config *i2c_config;
+ struct mutex lock;
+
+ bool is_stop_bit; /* set the stop bit for i2c transfer */
+ bool is_nak_bit; /* set the nak bit for i2c transfer */
+};
+
+#define to_cyusbs_i2c(a) container_of(a, struct cyusbs_i2c, i2c_adapter)
+
+static int cy_i2c_get_status(struct i2c_adapter *adapter, u8 *buf, u16 mode);
+static int cy_i2c_reset(struct i2c_adapter *adapter, u16 mode);
+
+static ssize_t i2c_read_status_show(struct device *d,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_adapter *adapter = to_i2c_adapter(d);
+
+ /* Updates buffer with 3 bytes status (hex data) */
+ return cy_i2c_get_status(adapter, buf, CY_I2C_MODE_READ);
+}
+
+static ssize_t i2c_write_status_show(struct device *d,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_adapter *adapter = to_i2c_adapter(d);
+
+ /* Updates buffer with 3 bytes status (hex data) */
+ return cy_i2c_get_status(adapter, buf, CY_I2C_MODE_WRITE);
+}
+
+static ssize_t i2c_read_reset_store(struct device *d,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ int ret;
+ long value;
+ struct i2c_adapter *adapter = to_i2c_adapter(d);
+
+ ret = kstrtol(buf, 0, &value);
+ if (ret)
+ return ret;
+
+ if (value != 1)
+ return -EINVAL;
+
+ ret = cy_i2c_reset(adapter, CY_I2C_MODE_READ);
+ if (!ret)
+ ret = count;
+
+ return ret;
+}
+
+static ssize_t i2c_write_reset_store(struct device *d,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ int ret;
+ long value;
+ struct i2c_adapter *adapter = to_i2c_adapter(d);
+
+ ret = kstrtol(buf, 0, &value);
+ if (ret)
+ return ret;
+
+ if (value != 1)
+ return -EINVAL;
+
+ ret = cy_i2c_reset(adapter, CY_I2C_MODE_WRITE);
+ if (!ret)
+ ret = count;
+
+ return ret;
+}
+
+static ssize_t is_stop_bit_show(struct device *d,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_adapter *adapter = to_i2c_adapter(d);
+ struct cyusbs_i2c *cy_i2c = to_cyusbs_i2c(adapter);
+
+ return scnprintf(buf, 3, "%d\n", cy_i2c->is_stop_bit);
+}
+
+static ssize_t is_stop_bit_store(struct device *d,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct i2c_adapter *adapter = to_i2c_adapter(d);
+ struct cyusbs_i2c *cy_i2c = to_cyusbs_i2c(adapter);
+ long value;
+ int ret;
+
+ ret = kstrtol(buf, 0, &value);
+ if (ret)
+ return ret;
+
+ if (value != 0 && value != 1)
+ return -EINVAL;
+
+ cy_i2c->is_stop_bit = (bool)value;
+
+ return count;
+}
+
+static ssize_t is_nak_bit_show(struct device *d,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_adapter *adapter = to_i2c_adapter(d);
+ struct cyusbs_i2c *cy_i2c = to_cyusbs_i2c(adapter);
+
+ return scnprintf(buf, 3, "%d\n", cy_i2c->is_nak_bit);
+}
+
+static ssize_t is_nak_bit_store(struct device *d,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct i2c_adapter *adapter = to_i2c_adapter(d);
+ struct cyusbs_i2c *cy_i2c = to_cyusbs_i2c(adapter);
+ long value;
+ int ret;
+
+ ret = kstrtol(buf, 0, &value);
+ if (ret)
+ return ret;
+
+ if (value != 0 && value != 1)
+ return -EINVAL;
+
+ cy_i2c->is_nak_bit = (bool)value;
+
+ return count;
+}
+
+static DEVICE_ATTR_RO(i2c_read_status);
+static DEVICE_ATTR_RO(i2c_write_status);
+static DEVICE_ATTR_WO(i2c_read_reset);
+static DEVICE_ATTR_WO(i2c_write_reset);
+static DEVICE_ATTR_RW(is_stop_bit);
+static DEVICE_ATTR_RW(is_nak_bit);
+
+static struct attribute *cyusbs_i2c_device_attrs[] = {
+ &dev_attr_i2c_read_status.attr,
+ &dev_attr_i2c_write_status.attr,
+ &dev_attr_i2c_read_reset.attr,
+ &dev_attr_i2c_write_reset.attr,
+ &dev_attr_is_stop_bit.attr,
+ &dev_attr_is_nak_bit.attr,
+ NULL
+};
+
+ATTRIBUTE_GROUPS(cyusbs_i2c_device);
+
+static int cy_i2c_get_status(struct i2c_adapter *adapter, u8 *buf, u16 mode)
+{
+ int ret;
+ u16 wIndex, wValue, scb_index;
+ u8 *data;
+ struct cyusbs23x *cyusbs = (struct cyusbs23x *)adapter->algo_data;
+ struct cyusbs_i2c *cy_i2c = to_cyusbs_i2c(adapter);
+
+ scb_index = cyusbs->intf_num & 0x01;
+ wValue = ((scb_index << CY_SCB_INDEX_SHIFT) | mode);
+ wIndex = 0;
+ data = kmalloc(CY_I2C_XFER_STATUS_LEN, GFP_KERNEL);
+ if (data == NULL)
+ return -ENOMEM;
+
+ mutex_lock(&cy_i2c->lock);
+ /* read the i2c transfer status */
+ ret = usb_control_msg(cyusbs->usb_dev,
+ usb_rcvctrlpipe(cyusbs->usb_dev, 0),
+ CY_I2C_GET_STATUS_CMD,
+ USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+ wValue, wIndex, data, CY_I2C_XFER_STATUS_LEN,
+ CY_USBS_CTRL_XFER_TIMEOUT);
+ mutex_unlock(&cy_i2c->lock);
+ if (ret != CY_I2C_XFER_STATUS_LEN) {
+ dev_err(&adapter->dev, "%s: failed to get status: %d",
+ __func__, ret);
+ ret = usb_translate_errors(ret);
+ goto status_error;
+ }
+
+ memcpy(buf, data, CY_I2C_XFER_STATUS_LEN);
+ buf[CY_I2C_XFER_STATUS_LEN] = 0;
+
+ dev_dbg(&adapter->dev, "%s: %02x %02x %02x\n", __func__,
+ buf[0], buf[1], buf[2]);
+
+status_error:
+ kfree(data);
+ return ret;
+}
+
+static int cy_i2c_reset(struct i2c_adapter *adapter, u16 mode)
+{
+ int ret;
+ u16 wIndex, wValue, scb_index;
+ struct cyusbs23x *cyusbs = (struct cyusbs23x *)adapter->algo_data;
+ struct cyusbs_i2c *cy_i2c = to_cyusbs_i2c(adapter);
+
+ scb_index = cyusbs->intf_num & 0x01;
+ wValue = ((scb_index << CY_SCB_INDEX_SHIFT) | mode);
+ wIndex = 0;
+
+ mutex_lock(&cy_i2c->lock);
+ ret = usb_control_msg(cyusbs->usb_dev,
+ usb_sndctrlpipe(cyusbs->usb_dev, 0),
+ CY_I2C_RESET_CMD,
+ USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
+ wValue, wIndex, NULL, 0, CY_USBS_CTRL_XFER_TIMEOUT);
+ mutex_unlock(&cy_i2c->lock);
+ if (ret) {
+ dev_err(&adapter->dev, "%s: failed to reset: %d",
+ __func__, ret);
+ ret = usb_translate_errors(ret);
+ }
+
+ return ret;
+}
+
+static int cy_i2c_recv_status(struct i2c_adapter *adapter)
+{
+ int ret, actual_len;
+ u8 *data;
+ struct cyusbs23x *cyusbs = (struct cyusbs23x *)adapter->algo_data;
+
+ data = kmalloc(CY_I2C_XFER_STATUS_LEN, GFP_KERNEL);
+ if (data == NULL)
+ return -ENOMEM;
+
+ /* read the i2c transfer status */
+ ret = usb_interrupt_msg(cyusbs->usb_dev,
+ usb_rcvintpipe(cyusbs->usb_dev, cyusbs->intr_in_ep_num),
+ data, CY_I2C_XFER_STATUS_LEN, &actual_len,
+ CY_USBS_INTR_XFER_TIMEOUT);
+ if (ret < 0) {
+ dev_err(&adapter->dev,
+ "Failed to read from interrupt ep: %d\n", ret);
+ ret = usb_translate_errors(ret);
+ goto intr_ep_error;
+ }
+
+ dev_dbg(&adapter->dev, "%s: %02x %02x %02x\n", __func__,
+ data[0], data[1], data[2]);
+
+ if (data[0] & 0x1)
+ ret = -ETIMEDOUT;
+
+intr_ep_error:
+ kfree(data);
+ return ret;
+}
+
+static int cy_get_i2c_config(struct cyusbs23x *cyusbs,
+ struct cyusbs_i2c *cy_i2c)
+{
+ int ret;
+ u16 scb_index;
+
+ scb_index = (cyusbs->intf_num & 0x01) << CY_SCB_INDEX_SHIFT;
+
+ ret = usb_control_msg(cyusbs->usb_dev,
+ usb_rcvctrlpipe(cyusbs->usb_dev, 0),
+ CY_I2C_GET_CONFIG_CMD,
+ USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+ scb_index, 0, cy_i2c->i2c_config,
+ sizeof(*cy_i2c->i2c_config), CY_USBS_CTRL_XFER_TIMEOUT);
+ if (ret != sizeof(*cy_i2c->i2c_config)) {
+ dev_err(&cyusbs->usb_intf->dev, "%s: %d\n",
+ __func__, ret);
+ ret = usb_translate_errors(ret);
+ goto config_error;
+ }
+
+ dev_dbg(&cyusbs->usb_intf->dev,
+ "%s: freq=%d, slave_addr=0x%02x, msb_first=%d, master=%d, ignore=%d, clock_stretch=%d, loopback=%d\n",
+ __func__, cy_i2c->i2c_config->frequency,
+ cy_i2c->i2c_config->slave_addr,
+ cy_i2c->i2c_config->is_msb_first,
+ cy_i2c->i2c_config->is_master,
+ cy_i2c->i2c_config->s_ignore,
+ cy_i2c->i2c_config->clock_stretch,
+ cy_i2c->i2c_config->is_loopback);
+
+config_error:
+ return ret;
+}
+
+static int cy_i2c_set_data_config(struct cyusbs23x *cyusbs,
+ struct cyusbs_i2c *cy_i2c, u16 slave_addr,
+ u16 length, u8 command)
+{
+ int ret;
+ u16 wIndex, wValue, scb_index;
+
+ scb_index = (cyusbs->intf_num & 0x01) << CY_SCB_INDEX_SHIFT;
+ slave_addr = (slave_addr & 0x7F);
+ wValue = scb_index | cy_i2c->is_stop_bit | cy_i2c->is_nak_bit << 1;
+ wValue |= (slave_addr << 8);
+ wIndex = length;
+
+ dev_dbg(&cy_i2c->i2c_adapter.dev,
+ "%s, cmd=0x%x, val=0x%x, idx=0x%x\n",
+ __func__, command, wValue, wIndex);
+
+ ret = usb_control_msg(cyusbs->usb_dev,
+ usb_sndctrlpipe(cyusbs->usb_dev, 0),
+ command, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
+ wValue, wIndex, NULL, 0, CY_USBS_CTRL_XFER_TIMEOUT);
+
+ return ret;
+}
+
+static int cy_i2c_read(struct i2c_adapter *adapter, struct i2c_msg *msgs)
+{
+ int ret;
+ int actual_read_len = 0;
+ struct cyusbs23x *cyusbs = (struct cyusbs23x *)adapter->algo_data;
+
+ dev_dbg(&adapter->dev, "%s\n", __func__);
+
+ ret = usb_bulk_msg(cyusbs->usb_dev,
+ usb_rcvbulkpipe(cyusbs->usb_dev, cyusbs->bulk_in_ep_num),
+ msgs[0].buf,
+ msgs[0].len,
+ &actual_read_len, CY_USBS_BULK_XFER_TIMEOUT);
+ if (ret)
+ dev_err(&adapter->dev,
+ "read %d/%d returned %d\n",
+ actual_read_len, msgs[0].len, ret);
+
+ ret = cy_i2c_recv_status(adapter);
+
+ return ret;
+}
+
+static int cy_i2c_write(struct i2c_adapter *adapter, struct i2c_msg *msgs)
+{
+ int ret;
+ int actual_write_len = 0;
+ struct cyusbs23x *cyusbs = (struct cyusbs23x *)adapter->algo_data;
+
+ dev_dbg(&adapter->dev, "%s\n", __func__);
+
+ ret = usb_bulk_msg(cyusbs->usb_dev,
+ usb_sndbulkpipe(cyusbs->usb_dev, cyusbs->bulk_out_ep_num),
+ msgs[0].buf,
+ msgs[0].len,
+ &actual_write_len, CY_USBS_BULK_XFER_TIMEOUT);
+ if (ret)
+ dev_err(&adapter->dev,
+ "write %d/%d returned %d\n",
+ actual_write_len, msgs[0].len, ret);
+
+ ret = cy_i2c_recv_status(adapter);
+
+ return ret;
+}
+
+static int cy_i2c_xfer(struct i2c_adapter *adapter,
+ struct i2c_msg *msgs, int num)
+{
+ int ret = 0;
+ struct cyusbs_i2c *cy_i2c;
+ struct cyusbs23x *cyusbs = (struct cyusbs23x *)adapter->algo_data;
+
+ dev_dbg(&adapter->dev, "%s\n", __func__);
+
+ if (num > 1) {
+ dev_err(&adapter->dev, "i2c_msg number is > 1\n");
+ return -EIO;
+ }
+
+ cy_i2c = to_cyusbs_i2c(adapter);
+
+ mutex_lock(&cy_i2c->lock);
+ if (msgs[0].flags & I2C_M_RD) {
+ dev_dbg(&adapter->dev,
+ "I2C read requested for addr 0x%02x, data length %d\n",
+ msgs[0].addr, msgs[0].len);
+
+ ret = cy_i2c_set_data_config(cyusbs, cy_i2c, msgs[0].addr,
+ msgs[0].len, CY_I2C_READ_CMD);
+ if (ret < 0) {
+ dev_err(&adapter->dev,
+ "Set Config (read) failed with %d\n", ret);
+ goto io_error;
+ }
+
+ ret = cy_i2c_read(adapter, msgs);
+ if (ret) {
+ dev_err(&adapter->dev,
+ "Read failed with error code %d\n", ret);
+ goto io_error;
+ }
+ } else {
+ dev_dbg(&adapter->dev,
+ "I2C write requested for addr 0x%02x, data length %d\n",
+ msgs[0].addr, msgs[0].len);
+
+ ret = cy_i2c_set_data_config(cyusbs, cy_i2c, msgs[0].addr,
+ msgs[0].len, CY_I2C_WRITE_CMD);
+ if (ret < 0) {
+ dev_err(&adapter->dev,
+ "Set Config (write) failed with %d\n", ret);
+ goto io_error;
+ }
+
+ ret = cy_i2c_write(adapter, msgs);
+ if (ret) {
+ dev_err(&adapter->dev,
+ "Write failed with error code %d\n", ret);
+ goto io_error;
+ }
+ }
+ mutex_unlock(&cy_i2c->lock);
+ return ret;
+
+io_error:
+ mutex_unlock(&cy_i2c->lock);
+ return ret;
+}
+
+static u32 cy_i2c_func(struct i2c_adapter *adapter)
+{
+ return I2C_FUNC_I2C;
+}
+
+static const struct i2c_algorithm i2c_cyusbs23x_algorithm = {
+ .master_xfer = cy_i2c_xfer,
+ .functionality = cy_i2c_func,
+};
+
+static int cyusbs23x_i2c_probe(struct platform_device *pdev)
+{
+ struct cyusbs23x *cyusbs;
+ struct cyusbs_i2c *cy_i2c;
+ int ret = 0;
+
+ dev_dbg(&pdev->dev, "%s\n", __func__);
+
+ cyusbs = dev_get_drvdata(pdev->dev.parent);
+
+ cy_i2c = devm_kzalloc(&pdev->dev, sizeof(*cy_i2c), GFP_KERNEL);
+ if (cy_i2c == NULL)
+ return -ENOMEM;
+
+ cy_i2c->i2c_config = devm_kzalloc(&pdev->dev,
+ sizeof(struct cyusbs_i2c_config),
+ GFP_KERNEL);
+ if (cy_i2c->i2c_config == NULL)
+ return -ENOMEM;
+
+ mutex_init(&cy_i2c->lock);
+ cy_i2c->is_stop_bit = 1;
+ cy_i2c->is_nak_bit = 1;
+
+ cy_i2c->i2c_adapter.owner = THIS_MODULE;
+ cy_i2c->i2c_adapter.class = I2C_CLASS_HWMON;
+ cy_i2c->i2c_adapter.algo = &i2c_cyusbs23x_algorithm;
+ cy_i2c->i2c_adapter.algo_data = cyusbs;
+ snprintf(cy_i2c->i2c_adapter.name, sizeof(cy_i2c->i2c_adapter.name),
+ "cyusbs23x_i2c at bus %03d dev %03d intf %03d",
+ cyusbs->usb_dev->bus->busnum, cyusbs->usb_dev->devnum,
+ cyusbs->intf_num);
+ cy_i2c->i2c_adapter.dev.parent = &pdev->dev;
+ cy_i2c->i2c_adapter.dev.groups = cyusbs_i2c_device_groups;
+
+ ret = cy_get_i2c_config(cyusbs, cy_i2c);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "error to get i2c config\n");
+ goto error;
+ }
+
+ if (!cy_i2c->i2c_config->is_master) {
+ ret = -ENODEV;
+ dev_err(&pdev->dev, "not an I2C master\n");
+ goto error;
+ }
+
+ ret = i2c_add_adapter(&cy_i2c->i2c_adapter);
+ if (ret != 0) {
+ dev_err(&pdev->dev, "failed to add i2c adapter\n");
+ goto error;
+ }
+
+ platform_set_drvdata(pdev, cy_i2c);
+
+ dev_dbg(&pdev->dev, "added I2C adapter\n");
+ return 0;
+
+error:
+ dev_err(&pdev->dev, "error occured %d\n", ret);
+ return ret;
+}
+
+static int cyusbs23x_i2c_remove(struct platform_device *pdev)
+{
+ struct cyusbs_i2c *cy_i2c = platform_get_drvdata(pdev);
+
+ dev_dbg(&pdev->dev, "%s\n", __func__);
+ i2c_del_adapter(&cy_i2c->i2c_adapter);
+ return 0;
+}
+
+static struct platform_driver cyusbs23x_i2c_driver = {
+ .driver.name = "cyusbs23x-i2c",
+ .probe = cyusbs23x_i2c_probe,
+ .remove = cyusbs23x_i2c_remove,
+};
+
+module_platform_driver(cyusbs23x_i2c_driver);
+
+MODULE_AUTHOR("Rajaram Regupathy <rera@cypress.com>");
+MODULE_AUTHOR("Muthu Mani <muth@cypress.com>");
+MODULE_DESCRIPTION("I2C adapter driver for CYUSBS23x");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:cyusbs23x-i2c");