[3/5] i2c: Add support for Intel LJCA USB I2C driver

Message ID	20230219183059.1029525-4-xiang.ye@intel.com
State	Superseded
Headers	show Return-Path: <linux-i2c-owner@vger.kernel.org> From: Ye Xiang <xiang.ye@intel.com> To: Lee Jones <lee@kernel.org>, Wolfram Sang <wsa@kernel.org>, Tyrone Ting <kfting@nuvoton.com>, Mark Brown <broonie@kernel.org>, Linus Walleij <linus.walleij@linaro.org>, Bartosz Golaszewski <brgl@bgdev.pl>, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, linux-gpio@vger.kernel.org Cc: srinivas.pandruvada@intel.com, heikki.krogerus@linux.intel.com, andriy.shevchenko@linux.intel.com, sakari.ailus@linux.intel.com, zhifeng.wang@intel.com, wentong.wu@intel.com, lixu.zhang@intel.com, Ye Xiang <xiang.ye@intel.com> Subject: [PATCH 3/5] i2c: Add support for Intel LJCA USB I2C driver Date: Mon, 20 Feb 2023 02:30:57 +0800 Message-Id: <20230219183059.1029525-4-xiang.ye@intel.com> In-Reply-To: <20230219183059.1029525-1-xiang.ye@intel.com> References: <20230219183059.1029525-1-xiang.ye@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	Add Intel LJCA device driver \| expand [0/5] Add Intel LJCA device driver [1/5] mfd: Add support for Intel LJCA device [2/5] gpio: Add support for Intel LJCA USB GPIO driver [3/5] i2c: Add support for Intel LJCA USB I2C driver [4/5] spi: Add support for Intel LJCA USB SPI driver [5/5] Documentation: Add ABI doc for attributes of LJCA device

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index a7bfddf08fa7..76ed5fb15493 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -1243,6 +1243,16 @@ config I2C_DLN2 This driver can also be built as a module. If so, the module will be called i2c-dln2. +config I2C_LJCA + tristate "I2C functionality of Intel La Jolla Cove Adapter" + depends on MFD_LJCA + help + If you say yes to this option, I2C functionality support of Intel + La Jolla Cove Adapter (LJCA) will be included. + + This driver can also be built as a module. If so, the module + will be called i2c-ljca. + config I2C_CP2615 tristate "Silicon Labs CP2615 USB sound card and I2C adapter" depends on USB diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index e73cdb1d2b5a..66a1fe79d0f6 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -131,6 +131,7 @@ obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o # External I2C/SMBus adapter drivers obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o obj-$(CONFIG_I2C_DLN2) += i2c-dln2.o +obj-$(CONFIG_I2C_LJCA) += i2c-ljca.o obj-$(CONFIG_I2C_CP2615) += i2c-cp2615.o obj-$(CONFIG_I2C_PARPORT) += i2c-parport.o obj-$(CONFIG_I2C_PCI1XXXX) += i2c-mchp-pci1xxxx.o diff --git a/drivers/i2c/busses/i2c-ljca.c b/drivers/i2c/busses/i2c-ljca.c new file mode 100644 index 000000000000..3250297c15b8 --- /dev/null +++ b/drivers/i2c/busses/i2c-ljca.c @@ -0,0 +1,357 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Intel La Jolla Cove Adapter USB-I2C driver + * + * Copyright (c) 2023, Intel Corporation. + */ + +#include <linux/bitfield.h> +#include <linux/bits.h> +#include <linux/dev_printk.h> +#include <linux/i2c.h> +#include <linux/mfd/ljca.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +/* I2C commands */ +enum ljca_i2c_cmd { + LJCA_I2C_INIT = 1, + LJCA_I2C_XFER, + LJCA_I2C_START, + LJCA_I2C_STOP, + LJCA_I2C_READ, + LJCA_I2C_WRITE, +}; + +enum ljca_xfer_type { + LJCA_I2C_READ_XFER_TYPE, + LJCA_I2C_WRITE_XFER_TYPE, +}; + +/* I2C r/w Flags */ +#define LJCA_I2C_SLAVE_TRANSFER_WRITE (0) +#define LJCA_I2C_SLAVE_TRANSFER_READ (1) + +/* I2C init flags */ +#define LJCA_I2C_INIT_FLAG_MODE BIT(0) +#define LJCA_I2C_INIT_FLAG_MODE_POLLING FIELD_PREP(LJCA_I2C_INIT_FLAG_MODE, 0) +#define LJCA_I2C_INIT_FLAG_MODE_INTERRUPT FIELD_PREP(LJCA_I2C_INIT_FLAG_MODE, 1) + +#define LJCA_I2C_INIT_FLAG_ADDR_16BIT BIT(0) + +#define LJCA_I2C_INIT_FLAG_FREQ GENMASK(2, 1) +#define LJCA_I2C_INIT_FLAG_FREQ_100K FIELD_PREP(LJCA_I2C_INIT_FLAG_FREQ, 0) +#define LJCA_I2C_INIT_FLAG_FREQ_400K FIELD_PREP(LJCA_I2C_INIT_FLAG_FREQ, 1) +#define LJCA_I2C_INIT_FLAG_FREQ_1M FIELD_PREP(LJCA_I2C_INIT_FLAG_FREQ, 2) + +/* I2C Transfer */ +struct i2c_xfer { + u8 id; + u8 slave; + u16 flag; /* speed, 8/16bit addr, addr increase, etc */ + u16 addr; + u16 len; + u8 data[]; +} __packed; + +/* I2C raw commands: Init/Start/Read/Write/Stop */ +struct i2c_rw_packet { + u8 id; + __le16 len; + u8 data[]; +} __packed; + +#define LJCA_I2C_BUF_SIZE 60 +#define LJCA_I2C_MAX_XFER_SIZE (LJCA_I2C_BUF_SIZE - sizeof(struct i2c_rw_packet)) + +struct ljca_i2c_dev { + struct platform_device *pdev; + struct ljca_i2c_info *i2c_info; + struct i2c_adapter adap; + + u8 obuf[LJCA_I2C_BUF_SIZE]; + u8 ibuf[LJCA_I2C_BUF_SIZE]; +}; + +static u8 ljca_i2c_format_slave_addr(u8 slave_addr, u8 type) +{ + return (slave_addr << 1) | (type == LJCA_I2C_READ_XFER_TYPE) ? + LJCA_I2C_SLAVE_TRANSFER_READ : + LJCA_I2C_SLAVE_TRANSFER_WRITE; +} + +static int ljca_i2c_init(struct ljca_i2c_dev *ljca_i2c, u8 id) +{ + struct i2c_rw_packet *w_packet = (struct i2c_rw_packet *)ljca_i2c->obuf; + + memset(w_packet, 0, sizeof(*w_packet)); + w_packet->id = id; + w_packet->data[0] = LJCA_I2C_INIT_FLAG_FREQ_400K; + w_packet->len = cpu_to_le16(sizeof(*w_packet->data)); + + return ljca_transfer(ljca_i2c->i2c_info->ljca, LJCA_I2C_INIT, w_packet, + struct_size(w_packet, data, 1), NULL, NULL); +} + +static int ljca_i2c_start(struct ljca_i2c_dev *ljca_i2c, u8 slave_addr, enum ljca_xfer_type type) +{ + struct i2c_rw_packet *w_packet = (struct i2c_rw_packet *)ljca_i2c->obuf; + struct i2c_rw_packet *r_packet = (struct i2c_rw_packet *)ljca_i2c->ibuf; + unsigned int ibuf_len = LJCA_I2C_BUF_SIZE; + int ret; + s16 rp_len; + + memset(w_packet, 0, sizeof(*w_packet)); + w_packet->id = ljca_i2c->i2c_info->id; + w_packet->data[0] = ljca_i2c_format_slave_addr(slave_addr, type); + w_packet->len = cpu_to_le16(sizeof(*w_packet->data)); + + ret = ljca_transfer(ljca_i2c->i2c_info->ljca, LJCA_I2C_START, w_packet, + struct_size(w_packet, data, 1), r_packet, &ibuf_len); + if (ret) + return ret; + + if (ibuf_len < sizeof(*r_packet)) + return -EIO; + + rp_len = le16_to_cpu(r_packet->len); + if (rp_len < 0 || r_packet->id != w_packet->id) { + dev_err(&ljca_i2c->adap.dev, "i2c start failed len:%d id:%d %d\n", rp_len, + r_packet->id, w_packet->id); + return -EIO; + } + + return 0; +} + +static int ljca_i2c_stop(struct ljca_i2c_dev *ljca_i2c, u8 slave_addr) +{ + struct i2c_rw_packet *w_packet = (struct i2c_rw_packet *)ljca_i2c->obuf; + struct i2c_rw_packet *r_packet = (struct i2c_rw_packet *)ljca_i2c->ibuf; + unsigned int ibuf_len = LJCA_I2C_BUF_SIZE; + int ret; + s16 rp_len; + + memset(w_packet, 0, sizeof(*w_packet)); + w_packet->id = ljca_i2c->i2c_info->id; + w_packet->data[0] = 0; + w_packet->len = cpu_to_le16(sizeof(*w_packet->data)); + + ret = ljca_transfer(ljca_i2c->i2c_info->ljca, LJCA_I2C_STOP, w_packet, + struct_size(w_packet, data, 1), r_packet, &ibuf_len); + if (ret) + return ret; + + if (ibuf_len < sizeof(*r_packet)) + return -EIO; + + rp_len = le16_to_cpu(r_packet->len); + if (rp_len < 0 || r_packet->id != w_packet->id) { + dev_err(&ljca_i2c->adap.dev, "i2c stop failed len:%d id:%d %d\n", rp_len, + r_packet->id, w_packet->id); + return -EIO; + } + + return 0; +} + +static int ljca_i2c_pure_read(struct ljca_i2c_dev *ljca_i2c, u8 *data, u8 len) +{ + struct i2c_rw_packet *w_packet = (struct i2c_rw_packet *)ljca_i2c->obuf; + struct i2c_rw_packet *r_packet = (struct i2c_rw_packet *)ljca_i2c->ibuf; + unsigned int ibuf_len = LJCA_I2C_BUF_SIZE; + int ret; + s16 rp_len; + + if (len > LJCA_I2C_MAX_XFER_SIZE) + return -EINVAL; + + memset(w_packet, 0, sizeof(*w_packet)); + w_packet->id = ljca_i2c->i2c_info->id; + w_packet->len = cpu_to_le16(len); + w_packet->data[0] = 0; + + ret = ljca_transfer(ljca_i2c->i2c_info->ljca, LJCA_I2C_READ, w_packet, + struct_size(w_packet, data, 1), r_packet, &ibuf_len); + if (ret) + return ret; + + if (ibuf_len < sizeof(*r_packet)) + return -EIO; + + rp_len = le16_to_cpu(r_packet->len); + if (rp_len != len || r_packet->id != w_packet->id) { + dev_err(&ljca_i2c->adap.dev, "i2c raw read failed len:%d id:%d %d\n", rp_len, + r_packet->id, w_packet->id); + return -EIO; + } + + memcpy(data, r_packet->data, len); + + return 0; +} + +static int ljca_i2c_read(struct ljca_i2c_dev *ljca_i2c, u8 slave_addr, u8 *data, + u8 len) +{ + int ret; + + ret = ljca_i2c_start(ljca_i2c, slave_addr, LJCA_I2C_READ_XFER_TYPE); + if (ret) + goto out_stop; + + ret = ljca_i2c_pure_read(ljca_i2c, data, len); + +out_stop: + ljca_i2c_stop(ljca_i2c, slave_addr); + return ret; +} + +static int ljca_i2c_pure_write(struct ljca_i2c_dev *ljca_i2c, u8 *data, u8 len) +{ + struct i2c_rw_packet *w_packet = (struct i2c_rw_packet *)ljca_i2c->obuf; + struct i2c_rw_packet *r_packet = (struct i2c_rw_packet *)ljca_i2c->ibuf; + unsigned int ibuf_len = LJCA_I2C_BUF_SIZE; + s16 rplen; + int ret; + + if (len > LJCA_I2C_MAX_XFER_SIZE) + return -EINVAL; + + memset(w_packet, 0, sizeof(*w_packet)); + w_packet->id = ljca_i2c->i2c_info->id; + w_packet->len = cpu_to_le16(len); + memcpy(w_packet->data, data, len); + + ret = ljca_transfer(ljca_i2c->i2c_info->ljca, LJCA_I2C_WRITE, w_packet, + struct_size(w_packet, data, len), r_packet, &ibuf_len); + if (ret) + return ret; + + if (ibuf_len < sizeof(*r_packet)) + return -EIO; + + rplen = le16_to_cpu(r_packet->len); + if (rplen != len || r_packet->id != w_packet->id) { + dev_err(&ljca_i2c->adap.dev, "i2c write failed len:%d id:%d/%d\n", rplen, + r_packet->id, w_packet->id); + return -EIO; + } + + return 0; +} + +static int ljca_i2c_write(struct ljca_i2c_dev *ljca_i2c, u8 slave_addr, u8 *data, u8 len) +{ + int ret; + + if (!data) + return -EINVAL; + + ret = ljca_i2c_start(ljca_i2c, slave_addr, LJCA_I2C_WRITE_XFER_TYPE); + if (ret) + goto out_stop; + + ret = ljca_i2c_pure_write(ljca_i2c, data, len); + +out_stop: + ljca_i2c_stop(ljca_i2c, slave_addr); + return ret; +} + +static int ljca_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msg, int num) +{ + struct ljca_i2c_dev *ljca_i2c; + struct i2c_msg *cur_msg; + int i, ret; + + ljca_i2c = i2c_get_adapdata(adapter); + if (!ljca_i2c) + return -EINVAL; + + for (i = 0; i < num; i++) { + cur_msg = &msg[i]; + if (cur_msg->flags & I2C_M_RD) + ret = ljca_i2c_read(ljca_i2c, cur_msg->addr, cur_msg->buf, cur_msg->len); + else + ret = ljca_i2c_write(ljca_i2c, cur_msg->addr, cur_msg->buf, cur_msg->len); + + if (ret) + return ret; + } + + return num; +} + +static u32 ljca_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_adapter_quirks ljca_i2c_quirks = { + .max_read_len = LJCA_I2C_MAX_XFER_SIZE, + .max_write_len = LJCA_I2C_MAX_XFER_SIZE, +}; + +static const struct i2c_algorithm ljca_i2c_algo = { + .master_xfer = ljca_i2c_xfer, + .functionality = ljca_i2c_func, +}; + +static int ljca_i2c_probe(struct platform_device *pdev) +{ + struct ljca_i2c_dev *ljca_i2c; + int ret; + + ljca_i2c = devm_kzalloc(&pdev->dev, sizeof(*ljca_i2c), GFP_KERNEL); + if (!ljca_i2c) + return -ENOMEM; + + ljca_i2c->pdev = pdev; + ljca_i2c->i2c_info = dev_get_platdata(&pdev->dev); + ljca_i2c->adap.owner = THIS_MODULE; + ljca_i2c->adap.class = I2C_CLASS_HWMON; + ljca_i2c->adap.algo = &ljca_i2c_algo; + ljca_i2c->adap.quirks = &ljca_i2c_quirks; + ljca_i2c->adap.dev.parent = &pdev->dev; + device_set_node(&ljca_i2c->adap.dev, dev_fwnode(&pdev->dev)); + i2c_set_adapdata(&ljca_i2c->adap, ljca_i2c); + snprintf(ljca_i2c->adap.name, sizeof(ljca_i2c->adap.name), "%s-%s-%d", + dev_name(&pdev->dev), dev_name(pdev->dev.parent), + ljca_i2c->i2c_info->id); + + platform_set_drvdata(pdev, ljca_i2c); + + ret = ljca_i2c_init(ljca_i2c, ljca_i2c->i2c_info->id); + if (ret) { + dev_err(&pdev->dev, "i2c init failed id:%d\n", ljca_i2c->i2c_info->id); + return -EIO; + } + + ret = devm_i2c_add_adapter(&pdev->dev, &ljca_i2c->adap); + if (ret) + return ret; + + return 0; +} + +#define LJCA_I2C_DRV_NAME "ljca-i2c" +static const struct platform_device_id ljca_i2c_id[] = { + { LJCA_I2C_DRV_NAME, 0 }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(platform, ljca_i2c_id); + +static struct platform_driver ljca_i2c_driver = { + .driver.name = LJCA_I2C_DRV_NAME, + .probe = ljca_i2c_probe, +}; + +module_platform_driver(ljca_i2c_driver); + +MODULE_AUTHOR("Ye Xiang <xiang.ye@intel.com>"); +MODULE_AUTHOR("Wang Zhifeng <zhifeng.wang@intel.com>"); +MODULE_AUTHOR("Zhang Lixu <lixu.zhang@intel.com>"); +MODULE_DESCRIPTION("Intel La Jolla Cove Adapter USB-I2C driver"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(LJCA);

[3/5] i2c: Add support for Intel LJCA USB I2C driver

Commit Message

Patch