HID: mcp2221: add usb to i2c-smbus host bridge
MCP2221 is a USB HID to I2C/SMbus host bridge device. This commit implements i2c and smbus host adapter support. 7-bit address and i2c multi-message transaction is also supported. Signed-off-by: Rishi Gupta <gupt21@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
parent
278de45e14
commit
67a95c2146
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@ -10236,6 +10236,13 @@ F: drivers/net/can/m_can/m_can.c
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F: drivers/net/can/m_can/m_can.h
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F: drivers/net/can/m_can/m_can_platform.c
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MCP2221A MICROCHIP USB-HID TO I2C BRIDGE DRIVER
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M: Rishi Gupta <gupt21@gmail.com>
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L: linux-i2c@vger.kernel.org
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L: linux-input@vger.kernel.org
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S: Maintained
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F: drivers/hid/hid-mcp2221.c
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MCP4018 AND MCP4531 MICROCHIP DIGITAL POTENTIOMETER DRIVERS
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M: Peter Rosin <peda@axentia.se>
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L: linux-iio@vger.kernel.org
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@ -1145,6 +1145,16 @@ config HID_ALPS
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Say Y here if you have a Alps touchpads over i2c-hid or usbhid
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and want support for its special functionalities.
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config HID_MCP2221
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tristate "Microchip MCP2221 HID USB-to-I2C/SMbus host support"
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depends on USB_HID && I2C
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---help---
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Provides I2C and SMBUS host adapter functionality over USB-HID
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through MCP2221 device.
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To compile this driver as a module, choose M here: the module
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will be called hid-mcp2221.ko.
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endmenu
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endif # HID
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@ -70,6 +70,7 @@ obj-$(CONFIG_HID_LOGITECH_HIDPP) += hid-logitech-hidpp.o
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obj-$(CONFIG_HID_MACALLY) += hid-macally.o
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obj-$(CONFIG_HID_MAGICMOUSE) += hid-magicmouse.o
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obj-$(CONFIG_HID_MALTRON) += hid-maltron.o
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obj-$(CONFIG_HID_MCP2221) += hid-mcp2221.o
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obj-$(CONFIG_HID_MAYFLASH) += hid-mf.o
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obj-$(CONFIG_HID_MICROSOFT) += hid-microsoft.o
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obj-$(CONFIG_HID_MONTEREY) += hid-monterey.o
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@ -819,6 +819,7 @@
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#define USB_DEVICE_ID_PICK16F1454 0x0042
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#define USB_DEVICE_ID_PICK16F1454_V2 0xf2f7
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#define USB_DEVICE_ID_LUXAFOR 0xf372
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#define USB_DEVICE_ID_MCP2221 0x00dd
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#define USB_VENDOR_ID_MICROSOFT 0x045e
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#define USB_DEVICE_ID_SIDEWINDER_GV 0x003b
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742
drivers/hid/hid-mcp2221.c
Normal file
742
drivers/hid/hid-mcp2221.c
Normal file
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@ -0,0 +1,742 @@
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// SPDX-License-Identifier: GPL-2.0-only
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/*
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* MCP2221A - Microchip USB to I2C Host Protocol Bridge
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*
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* Copyright (c) 2020, Rishi Gupta <gupt21@gmail.com>
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*
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* Datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/20005565B.pdf
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*/
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#include <linux/module.h>
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#include <linux/err.h>
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#include <linux/mutex.h>
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#include <linux/completion.h>
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#include <linux/delay.h>
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#include <linux/hid.h>
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#include <linux/hidraw.h>
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#include <linux/i2c.h>
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#include "hid-ids.h"
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/* Commands codes in a raw output report */
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enum {
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MCP2221_I2C_WR_DATA = 0x90,
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MCP2221_I2C_WR_NO_STOP = 0x94,
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MCP2221_I2C_RD_DATA = 0x91,
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MCP2221_I2C_RD_RPT_START = 0x93,
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MCP2221_I2C_GET_DATA = 0x40,
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MCP2221_I2C_PARAM_OR_STATUS = 0x10,
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MCP2221_I2C_SET_SPEED = 0x20,
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MCP2221_I2C_CANCEL = 0x10,
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};
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/* Response codes in a raw input report */
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enum {
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MCP2221_SUCCESS = 0x00,
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MCP2221_I2C_ENG_BUSY = 0x01,
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MCP2221_I2C_START_TOUT = 0x12,
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MCP2221_I2C_STOP_TOUT = 0x62,
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MCP2221_I2C_WRADDRL_TOUT = 0x23,
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MCP2221_I2C_WRDATA_TOUT = 0x44,
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MCP2221_I2C_WRADDRL_NACK = 0x25,
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MCP2221_I2C_MASK_ADDR_NACK = 0x40,
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MCP2221_I2C_WRADDRL_SEND = 0x21,
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MCP2221_I2C_ADDR_NACK = 0x25,
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MCP2221_I2C_READ_COMPL = 0x55,
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};
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/*
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* There is no way to distinguish responses. Therefore next command
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* is sent only after response to previous has been received. Mutex
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* lock is used for this purpose mainly.
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*/
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struct mcp2221 {
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struct hid_device *hdev;
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struct i2c_adapter adapter;
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struct mutex lock;
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struct completion wait_in_report;
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u8 *rxbuf;
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u8 txbuf[64];
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int rxbuf_idx;
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int status;
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u8 cur_i2c_clk_div;
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};
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/*
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* Default i2c bus clock frequency 400 kHz. Modify this if you
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* want to set some other frequency (min 50 kHz - max 400 kHz).
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*/
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static uint i2c_clk_freq = 400;
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/* Synchronously send output report to the device */
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static int mcp_send_report(struct mcp2221 *mcp,
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u8 *out_report, size_t len)
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{
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u8 *buf;
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int ret;
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buf = kmemdup(out_report, len, GFP_KERNEL);
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if (!buf)
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return -ENOMEM;
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/* mcp2221 uses interrupt endpoint for out reports */
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ret = hid_hw_output_report(mcp->hdev, buf, len);
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kfree(buf);
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if (ret < 0)
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return ret;
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return 0;
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}
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/*
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* Send o/p report to the device and wait for i/p report to be
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* received from the device. If the device does not respond,
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* we timeout.
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*/
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static int mcp_send_data_req_status(struct mcp2221 *mcp,
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u8 *out_report, int len)
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{
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int ret;
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unsigned long t;
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reinit_completion(&mcp->wait_in_report);
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ret = mcp_send_report(mcp, out_report, len);
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if (ret)
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return ret;
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t = wait_for_completion_timeout(&mcp->wait_in_report,
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msecs_to_jiffies(4000));
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if (!t)
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return -ETIMEDOUT;
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return mcp->status;
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}
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/* Check pass/fail for actual communication with i2c slave */
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static int mcp_chk_last_cmd_status(struct mcp2221 *mcp)
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{
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memset(mcp->txbuf, 0, 8);
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mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
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return mcp_send_data_req_status(mcp, mcp->txbuf, 8);
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}
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/* Cancels last command releasing i2c bus just in case occupied */
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static int mcp_cancel_last_cmd(struct mcp2221 *mcp)
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{
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memset(mcp->txbuf, 0, 8);
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mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
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mcp->txbuf[2] = MCP2221_I2C_CANCEL;
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return mcp_send_data_req_status(mcp, mcp->txbuf, 8);
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}
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static int mcp_set_i2c_speed(struct mcp2221 *mcp)
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{
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int ret;
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memset(mcp->txbuf, 0, 8);
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mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
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mcp->txbuf[3] = MCP2221_I2C_SET_SPEED;
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mcp->txbuf[4] = mcp->cur_i2c_clk_div;
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ret = mcp_send_data_req_status(mcp, mcp->txbuf, 8);
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if (ret) {
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/* Small delay is needed here */
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usleep_range(980, 1000);
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mcp_cancel_last_cmd(mcp);
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}
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return 0;
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}
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/*
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* An output report can contain minimum 1 and maximum 60 user data
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* bytes. If the number of data bytes is more then 60, we send it
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* in chunks of 60 bytes. Last chunk may contain exactly 60 or less
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* bytes. Total number of bytes is informed in very first report to
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* mcp2221, from that point onwards it first collect all the data
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* from host and then send to i2c slave device.
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*/
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static int mcp_i2c_write(struct mcp2221 *mcp,
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struct i2c_msg *msg, int type, u8 last_status)
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{
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int ret, len, idx, sent;
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idx = 0;
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sent = 0;
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if (msg->len < 60)
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len = msg->len;
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else
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len = 60;
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do {
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mcp->txbuf[0] = type;
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mcp->txbuf[1] = msg->len & 0xff;
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mcp->txbuf[2] = msg->len >> 8;
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mcp->txbuf[3] = (u8)(msg->addr << 1);
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memcpy(&mcp->txbuf[4], &msg->buf[idx], len);
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ret = mcp_send_data_req_status(mcp, mcp->txbuf, len + 4);
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if (ret)
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return ret;
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usleep_range(980, 1000);
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if (last_status) {
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ret = mcp_chk_last_cmd_status(mcp);
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if (ret)
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return ret;
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}
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sent = sent + len;
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if (sent >= msg->len)
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break;
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idx = idx + len;
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if ((msg->len - sent) < 60)
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len = msg->len - sent;
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else
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len = 60;
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/*
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* Testing shows delay is needed between successive writes
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* otherwise next write fails on first-try from i2c core.
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* This value is obtained through automated stress testing.
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*/
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usleep_range(980, 1000);
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} while (len > 0);
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return ret;
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}
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/*
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* Device reads all data (0 - 65535 bytes) from i2c slave device and
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* stores it in device itself. This data is read back from device to
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* host in multiples of 60 bytes using input reports.
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*/
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static int mcp_i2c_smbus_read(struct mcp2221 *mcp,
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struct i2c_msg *msg, int type, u16 smbus_addr,
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u8 smbus_len, u8 *smbus_buf)
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{
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int ret;
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u16 total_len;
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mcp->txbuf[0] = type;
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if (msg) {
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mcp->txbuf[1] = msg->len & 0xff;
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mcp->txbuf[2] = msg->len >> 8;
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mcp->txbuf[3] = (u8)(msg->addr << 1);
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total_len = msg->len;
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mcp->rxbuf = msg->buf;
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} else {
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mcp->txbuf[1] = smbus_len;
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mcp->txbuf[2] = 0;
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mcp->txbuf[3] = (u8)(smbus_addr << 1);
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total_len = smbus_len;
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mcp->rxbuf = smbus_buf;
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}
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ret = mcp_send_data_req_status(mcp, mcp->txbuf, 4);
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if (ret)
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return ret;
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mcp->rxbuf_idx = 0;
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do {
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memset(mcp->txbuf, 0, 4);
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mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
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ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
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if (ret)
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return ret;
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ret = mcp_chk_last_cmd_status(mcp);
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if (ret)
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return ret;
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usleep_range(980, 1000);
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} while (mcp->rxbuf_idx < total_len);
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return ret;
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}
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static int mcp_i2c_xfer(struct i2c_adapter *adapter,
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struct i2c_msg msgs[], int num)
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{
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int ret;
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struct mcp2221 *mcp = i2c_get_adapdata(adapter);
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hid_hw_power(mcp->hdev, PM_HINT_FULLON);
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mutex_lock(&mcp->lock);
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/* Setting speed before every transaction is required for mcp2221 */
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ret = mcp_set_i2c_speed(mcp);
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if (ret)
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goto exit;
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if (num == 1) {
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if (msgs->flags & I2C_M_RD) {
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ret = mcp_i2c_smbus_read(mcp, msgs, MCP2221_I2C_RD_DATA,
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0, 0, NULL);
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} else {
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ret = mcp_i2c_write(mcp, msgs, MCP2221_I2C_WR_DATA, 1);
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}
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if (ret)
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goto exit;
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ret = num;
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} else if (num == 2) {
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/* Ex transaction; send reg address and read its contents */
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if (msgs[0].addr == msgs[1].addr &&
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!(msgs[0].flags & I2C_M_RD) &&
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(msgs[1].flags & I2C_M_RD)) {
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ret = mcp_i2c_write(mcp, &msgs[0],
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MCP2221_I2C_WR_NO_STOP, 0);
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if (ret)
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goto exit;
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ret = mcp_i2c_smbus_read(mcp, &msgs[1],
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MCP2221_I2C_RD_RPT_START,
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0, 0, NULL);
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if (ret)
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goto exit;
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ret = num;
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} else {
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dev_err(&adapter->dev,
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"unsupported multi-msg i2c transaction\n");
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ret = -EOPNOTSUPP;
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}
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} else {
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dev_err(&adapter->dev,
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"unsupported multi-msg i2c transaction\n");
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ret = -EOPNOTSUPP;
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}
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exit:
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hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
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mutex_unlock(&mcp->lock);
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return ret;
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}
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static int mcp_smbus_write(struct mcp2221 *mcp, u16 addr,
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u8 command, u8 *buf, u8 len, int type,
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u8 last_status)
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{
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int data_len, ret;
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mcp->txbuf[0] = type;
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mcp->txbuf[1] = len + 1; /* 1 is due to command byte itself */
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mcp->txbuf[2] = 0;
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mcp->txbuf[3] = (u8)(addr << 1);
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mcp->txbuf[4] = command;
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switch (len) {
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case 0:
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data_len = 5;
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break;
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case 1:
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mcp->txbuf[5] = buf[0];
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data_len = 6;
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break;
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case 2:
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mcp->txbuf[5] = buf[0];
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mcp->txbuf[6] = buf[1];
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data_len = 7;
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break;
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default:
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memcpy(&mcp->txbuf[5], buf, len);
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data_len = len + 5;
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}
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ret = mcp_send_data_req_status(mcp, mcp->txbuf, data_len);
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if (ret)
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return ret;
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if (last_status) {
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usleep_range(980, 1000);
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ret = mcp_chk_last_cmd_status(mcp);
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if (ret)
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return ret;
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}
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return ret;
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}
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static int mcp_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
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unsigned short flags, char read_write,
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u8 command, int size,
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union i2c_smbus_data *data)
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{
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int ret;
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struct mcp2221 *mcp = i2c_get_adapdata(adapter);
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hid_hw_power(mcp->hdev, PM_HINT_FULLON);
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mutex_lock(&mcp->lock);
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ret = mcp_set_i2c_speed(mcp);
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if (ret)
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goto exit;
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switch (size) {
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case I2C_SMBUS_QUICK:
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if (read_write == I2C_SMBUS_READ)
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ret = mcp_i2c_smbus_read(mcp, NULL, MCP2221_I2C_RD_DATA,
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addr, 0, &data->byte);
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else
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ret = mcp_smbus_write(mcp, addr, command, NULL,
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0, MCP2221_I2C_WR_DATA, 1);
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break;
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case I2C_SMBUS_BYTE:
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if (read_write == I2C_SMBUS_READ)
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ret = mcp_i2c_smbus_read(mcp, NULL, MCP2221_I2C_RD_DATA,
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addr, 1, &data->byte);
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else
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ret = mcp_smbus_write(mcp, addr, command, NULL,
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0, MCP2221_I2C_WR_DATA, 1);
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break;
|
||||
case I2C_SMBUS_BYTE_DATA:
|
||||
if (read_write == I2C_SMBUS_READ) {
|
||||
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
||||
0, MCP2221_I2C_WR_NO_STOP, 0);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
ret = mcp_i2c_smbus_read(mcp, NULL,
|
||||
MCP2221_I2C_RD_RPT_START,
|
||||
addr, 1, &data->byte);
|
||||
} else {
|
||||
ret = mcp_smbus_write(mcp, addr, command, &data->byte,
|
||||
1, MCP2221_I2C_WR_DATA, 1);
|
||||
}
|
||||
break;
|
||||
case I2C_SMBUS_WORD_DATA:
|
||||
if (read_write == I2C_SMBUS_READ) {
|
||||
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
||||
0, MCP2221_I2C_WR_NO_STOP, 0);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
ret = mcp_i2c_smbus_read(mcp, NULL,
|
||||
MCP2221_I2C_RD_RPT_START,
|
||||
addr, 2, (u8 *)&data->word);
|
||||
} else {
|
||||
ret = mcp_smbus_write(mcp, addr, command,
|
||||
(u8 *)&data->word, 2,
|
||||
MCP2221_I2C_WR_DATA, 1);
|
||||
}
|
||||
break;
|
||||
case I2C_SMBUS_BLOCK_DATA:
|
||||
if (read_write == I2C_SMBUS_READ) {
|
||||
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
||||
0, MCP2221_I2C_WR_NO_STOP, 1);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
mcp->rxbuf_idx = 0;
|
||||
mcp->rxbuf = data->block;
|
||||
mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
|
||||
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
|
||||
if (ret)
|
||||
goto exit;
|
||||
} else {
|
||||
if (!data->block[0]) {
|
||||
ret = -EINVAL;
|
||||
goto exit;
|
||||
}
|
||||
ret = mcp_smbus_write(mcp, addr, command, data->block,
|
||||
data->block[0] + 1,
|
||||
MCP2221_I2C_WR_DATA, 1);
|
||||
}
|
||||
break;
|
||||
case I2C_SMBUS_I2C_BLOCK_DATA:
|
||||
if (read_write == I2C_SMBUS_READ) {
|
||||
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
||||
0, MCP2221_I2C_WR_NO_STOP, 1);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
mcp->rxbuf_idx = 0;
|
||||
mcp->rxbuf = data->block;
|
||||
mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
|
||||
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
|
||||
if (ret)
|
||||
goto exit;
|
||||
} else {
|
||||
if (!data->block[0]) {
|
||||
ret = -EINVAL;
|
||||
goto exit;
|
||||
}
|
||||
ret = mcp_smbus_write(mcp, addr, command,
|
||||
&data->block[1], data->block[0],
|
||||
MCP2221_I2C_WR_DATA, 1);
|
||||
}
|
||||
break;
|
||||
case I2C_SMBUS_PROC_CALL:
|
||||
ret = mcp_smbus_write(mcp, addr, command,
|
||||
(u8 *)&data->word,
|
||||
2, MCP2221_I2C_WR_NO_STOP, 0);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
ret = mcp_i2c_smbus_read(mcp, NULL,
|
||||
MCP2221_I2C_RD_RPT_START,
|
||||
addr, 2, (u8 *)&data->word);
|
||||
break;
|
||||
case I2C_SMBUS_BLOCK_PROC_CALL:
|
||||
ret = mcp_smbus_write(mcp, addr, command, data->block,
|
||||
data->block[0] + 1,
|
||||
MCP2221_I2C_WR_NO_STOP, 0);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
ret = mcp_i2c_smbus_read(mcp, NULL,
|
||||
MCP2221_I2C_RD_RPT_START,
|
||||
addr, I2C_SMBUS_BLOCK_MAX,
|
||||
data->block);
|
||||
break;
|
||||
default:
|
||||
dev_err(&mcp->adapter.dev,
|
||||
"unsupported smbus transaction size:%d\n", size);
|
||||
ret = -EOPNOTSUPP;
|
||||
}
|
||||
|
||||
exit:
|
||||
hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
|
||||
mutex_unlock(&mcp->lock);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static u32 mcp_i2c_func(struct i2c_adapter *adapter)
|
||||
{
|
||||
return I2C_FUNC_I2C |
|
||||
I2C_FUNC_SMBUS_READ_BLOCK_DATA |
|
||||
I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
|
||||
(I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_PEC);
|
||||
}
|
||||
|
||||
static const struct i2c_algorithm mcp_i2c_algo = {
|
||||
.master_xfer = mcp_i2c_xfer,
|
||||
.smbus_xfer = mcp_smbus_xfer,
|
||||
.functionality = mcp_i2c_func,
|
||||
};
|
||||
|
||||
/* Gives current state of i2c engine inside mcp2221 */
|
||||
static int mcp_get_i2c_eng_state(struct mcp2221 *mcp,
|
||||
u8 *data, u8 idx)
|
||||
{
|
||||
int ret;
|
||||
|
||||
switch (data[idx]) {
|
||||
case MCP2221_I2C_WRADDRL_NACK:
|
||||
case MCP2221_I2C_WRADDRL_SEND:
|
||||
ret = -ENXIO;
|
||||
break;
|
||||
case MCP2221_I2C_START_TOUT:
|
||||
case MCP2221_I2C_STOP_TOUT:
|
||||
case MCP2221_I2C_WRADDRL_TOUT:
|
||||
case MCP2221_I2C_WRDATA_TOUT:
|
||||
ret = -ETIMEDOUT;
|
||||
break;
|
||||
case MCP2221_I2C_ENG_BUSY:
|
||||
ret = -EAGAIN;
|
||||
break;
|
||||
case MCP2221_SUCCESS:
|
||||
ret = 0x00;
|
||||
break;
|
||||
default:
|
||||
ret = -EIO;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* MCP2221 uses interrupt endpoint for input reports. This function
|
||||
* is called by HID layer when it receives i/p report from mcp2221,
|
||||
* which is actually a response to the previously sent command.
|
||||
*
|
||||
* MCP2221A firmware specific return codes are parsed and 0 or
|
||||
* appropriate negative error code is returned. Delayed response
|
||||
* results in timeout error and stray reponses results in -EIO.
|
||||
*/
|
||||
static int mcp2221_raw_event(struct hid_device *hdev,
|
||||
struct hid_report *report, u8 *data, int size)
|
||||
{
|
||||
u8 *buf;
|
||||
struct mcp2221 *mcp = hid_get_drvdata(hdev);
|
||||
|
||||
switch (data[0]) {
|
||||
|
||||
case MCP2221_I2C_WR_DATA:
|
||||
case MCP2221_I2C_WR_NO_STOP:
|
||||
case MCP2221_I2C_RD_DATA:
|
||||
case MCP2221_I2C_RD_RPT_START:
|
||||
switch (data[1]) {
|
||||
case MCP2221_SUCCESS:
|
||||
mcp->status = 0;
|
||||
break;
|
||||
default:
|
||||
mcp->status = mcp_get_i2c_eng_state(mcp, data, 2);
|
||||
}
|
||||
complete(&mcp->wait_in_report);
|
||||
break;
|
||||
|
||||
case MCP2221_I2C_PARAM_OR_STATUS:
|
||||
switch (data[1]) {
|
||||
case MCP2221_SUCCESS:
|
||||
if ((mcp->txbuf[3] == MCP2221_I2C_SET_SPEED) &&
|
||||
(data[3] != MCP2221_I2C_SET_SPEED)) {
|
||||
mcp->status = -EAGAIN;
|
||||
break;
|
||||
}
|
||||
if (data[20] & MCP2221_I2C_MASK_ADDR_NACK) {
|
||||
mcp->status = -ENXIO;
|
||||
break;
|
||||
}
|
||||
mcp->status = mcp_get_i2c_eng_state(mcp, data, 8);
|
||||
break;
|
||||
default:
|
||||
mcp->status = -EIO;
|
||||
}
|
||||
complete(&mcp->wait_in_report);
|
||||
break;
|
||||
|
||||
case MCP2221_I2C_GET_DATA:
|
||||
switch (data[1]) {
|
||||
case MCP2221_SUCCESS:
|
||||
if (data[2] == MCP2221_I2C_ADDR_NACK) {
|
||||
mcp->status = -ENXIO;
|
||||
break;
|
||||
}
|
||||
if (!mcp_get_i2c_eng_state(mcp, data, 2)
|
||||
&& (data[3] == 0)) {
|
||||
mcp->status = 0;
|
||||
break;
|
||||
}
|
||||
if (data[3] == 127) {
|
||||
mcp->status = -EIO;
|
||||
break;
|
||||
}
|
||||
if (data[2] == MCP2221_I2C_READ_COMPL) {
|
||||
buf = mcp->rxbuf;
|
||||
memcpy(&buf[mcp->rxbuf_idx], &data[4], data[3]);
|
||||
mcp->rxbuf_idx = mcp->rxbuf_idx + data[3];
|
||||
mcp->status = 0;
|
||||
break;
|
||||
}
|
||||
mcp->status = -EIO;
|
||||
break;
|
||||
default:
|
||||
mcp->status = -EIO;
|
||||
}
|
||||
complete(&mcp->wait_in_report);
|
||||
break;
|
||||
|
||||
default:
|
||||
mcp->status = -EIO;
|
||||
complete(&mcp->wait_in_report);
|
||||
}
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int mcp2221_probe(struct hid_device *hdev,
|
||||
const struct hid_device_id *id)
|
||||
{
|
||||
int ret;
|
||||
struct mcp2221 *mcp;
|
||||
|
||||
mcp = devm_kzalloc(&hdev->dev, sizeof(*mcp), GFP_KERNEL);
|
||||
if (!mcp)
|
||||
return -ENOMEM;
|
||||
|
||||
ret = hid_parse(hdev);
|
||||
if (ret) {
|
||||
hid_err(hdev, "can't parse reports\n");
|
||||
return ret;
|
||||
}
|
||||
|
||||
ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
|
||||
if (ret) {
|
||||
hid_err(hdev, "can't start hardware\n");
|
||||
return ret;
|
||||
}
|
||||
|
||||
ret = hid_hw_open(hdev);
|
||||
if (ret) {
|
||||
hid_err(hdev, "can't open device\n");
|
||||
goto err_hstop;
|
||||
}
|
||||
|
||||
mutex_init(&mcp->lock);
|
||||
init_completion(&mcp->wait_in_report);
|
||||
hid_set_drvdata(hdev, mcp);
|
||||
mcp->hdev = hdev;
|
||||
|
||||
/* Set I2C bus clock diviser */
|
||||
if (i2c_clk_freq > 400)
|
||||
i2c_clk_freq = 400;
|
||||
if (i2c_clk_freq < 50)
|
||||
i2c_clk_freq = 50;
|
||||
mcp->cur_i2c_clk_div = (12000000 / (i2c_clk_freq * 1000)) - 3;
|
||||
|
||||
mcp->adapter.owner = THIS_MODULE;
|
||||
mcp->adapter.class = I2C_CLASS_HWMON;
|
||||
mcp->adapter.algo = &mcp_i2c_algo;
|
||||
mcp->adapter.retries = 1;
|
||||
mcp->adapter.dev.parent = &hdev->dev;
|
||||
snprintf(mcp->adapter.name, sizeof(mcp->adapter.name),
|
||||
"MCP2221 usb-i2c bridge on hidraw%d",
|
||||
((struct hidraw *)hdev->hidraw)->minor);
|
||||
|
||||
ret = i2c_add_adapter(&mcp->adapter);
|
||||
if (ret) {
|
||||
hid_err(hdev, "can't add usb-i2c adapter: %d\n", ret);
|
||||
goto err_i2c;
|
||||
}
|
||||
i2c_set_adapdata(&mcp->adapter, mcp);
|
||||
|
||||
return 0;
|
||||
|
||||
err_i2c:
|
||||
hid_hw_close(mcp->hdev);
|
||||
err_hstop:
|
||||
hid_hw_stop(mcp->hdev);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void mcp2221_remove(struct hid_device *hdev)
|
||||
{
|
||||
struct mcp2221 *mcp = hid_get_drvdata(hdev);
|
||||
|
||||
i2c_del_adapter(&mcp->adapter);
|
||||
hid_hw_close(mcp->hdev);
|
||||
hid_hw_stop(mcp->hdev);
|
||||
}
|
||||
|
||||
static const struct hid_device_id mcp2221_devices[] = {
|
||||
{ HID_USB_DEVICE(USB_VENDOR_ID_MICROCHIP, USB_DEVICE_ID_MCP2221) },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(hid, mcp2221_devices);
|
||||
|
||||
static struct hid_driver mcp2221_driver = {
|
||||
.name = "mcp2221",
|
||||
.id_table = mcp2221_devices,
|
||||
.probe = mcp2221_probe,
|
||||
.remove = mcp2221_remove,
|
||||
.raw_event = mcp2221_raw_event,
|
||||
};
|
||||
|
||||
/* Register with HID core */
|
||||
module_hid_driver(mcp2221_driver);
|
||||
|
||||
MODULE_AUTHOR("Rishi Gupta <gupt21@gmail.com>");
|
||||
MODULE_DESCRIPTION("MCP2221 Microchip HID USB to I2C master bridge");
|
||||
MODULE_LICENSE("GPL v2");
|
Loading…
Reference in a new issue