1caee8e38SWentong Wu // SPDX-License-Identifier: GPL-2.0-only 2caee8e38SWentong Wu /* 3caee8e38SWentong Wu * Intel La Jolla Cove Adapter USB-SPI driver 4caee8e38SWentong Wu * 5caee8e38SWentong Wu * Copyright (c) 2023, Intel Corporation. 6caee8e38SWentong Wu */ 7caee8e38SWentong Wu 8caee8e38SWentong Wu #include <linux/auxiliary_bus.h> 9caee8e38SWentong Wu #include <linux/bitfield.h> 10caee8e38SWentong Wu #include <linux/bits.h> 11caee8e38SWentong Wu #include <linux/dev_printk.h> 12caee8e38SWentong Wu #include <linux/module.h> 13caee8e38SWentong Wu #include <linux/spi/spi.h> 14caee8e38SWentong Wu #include <linux/usb/ljca.h> 15caee8e38SWentong Wu 16caee8e38SWentong Wu #define LJCA_SPI_BUS_MAX_HZ 48000000 17caee8e38SWentong Wu 18caee8e38SWentong Wu #define LJCA_SPI_BUF_SIZE 60u 19caee8e38SWentong Wu #define LJCA_SPI_MAX_XFER_SIZE \ 20caee8e38SWentong Wu (LJCA_SPI_BUF_SIZE - sizeof(struct ljca_spi_xfer_packet)) 21caee8e38SWentong Wu 22caee8e38SWentong Wu #define LJCA_SPI_CLK_MODE_POLARITY BIT(0) 23caee8e38SWentong Wu #define LJCA_SPI_CLK_MODE_PHASE BIT(1) 24caee8e38SWentong Wu 25caee8e38SWentong Wu #define LJCA_SPI_XFER_INDICATOR_ID GENMASK(5, 0) 26caee8e38SWentong Wu #define LJCA_SPI_XFER_INDICATOR_CMPL BIT(6) 27caee8e38SWentong Wu #define LJCA_SPI_XFER_INDICATOR_INDEX BIT(7) 28caee8e38SWentong Wu 29caee8e38SWentong Wu /* SPI commands */ 30caee8e38SWentong Wu enum ljca_spi_cmd { 31caee8e38SWentong Wu LJCA_SPI_INIT = 1, 32caee8e38SWentong Wu LJCA_SPI_READ, 33caee8e38SWentong Wu LJCA_SPI_WRITE, 34caee8e38SWentong Wu LJCA_SPI_WRITEREAD, 35caee8e38SWentong Wu LJCA_SPI_DEINIT, 36caee8e38SWentong Wu }; 37caee8e38SWentong Wu 38caee8e38SWentong Wu enum { 39caee8e38SWentong Wu LJCA_SPI_BUS_SPEED_24M, 40caee8e38SWentong Wu LJCA_SPI_BUS_SPEED_12M, 41caee8e38SWentong Wu LJCA_SPI_BUS_SPEED_8M, 42caee8e38SWentong Wu LJCA_SPI_BUS_SPEED_6M, 43caee8e38SWentong Wu LJCA_SPI_BUS_SPEED_4_8M, /*4.8MHz*/ 44caee8e38SWentong Wu LJCA_SPI_BUS_SPEED_MIN = LJCA_SPI_BUS_SPEED_4_8M, 45caee8e38SWentong Wu }; 46caee8e38SWentong Wu 47caee8e38SWentong Wu enum { 48caee8e38SWentong Wu LJCA_SPI_CLOCK_LOW_POLARITY, 49caee8e38SWentong Wu LJCA_SPI_CLOCK_HIGH_POLARITY, 50caee8e38SWentong Wu }; 51caee8e38SWentong Wu 52caee8e38SWentong Wu enum { 53caee8e38SWentong Wu LJCA_SPI_CLOCK_FIRST_PHASE, 54caee8e38SWentong Wu LJCA_SPI_CLOCK_SECOND_PHASE, 55caee8e38SWentong Wu }; 56caee8e38SWentong Wu 57caee8e38SWentong Wu struct ljca_spi_init_packet { 58caee8e38SWentong Wu u8 index; 59caee8e38SWentong Wu u8 speed; 60caee8e38SWentong Wu u8 mode; 61caee8e38SWentong Wu } __packed; 62caee8e38SWentong Wu 63caee8e38SWentong Wu struct ljca_spi_xfer_packet { 64caee8e38SWentong Wu u8 indicator; 65caee8e38SWentong Wu u8 len; 66caee8e38SWentong Wu u8 data[] __counted_by(len); 67caee8e38SWentong Wu } __packed; 68caee8e38SWentong Wu 69caee8e38SWentong Wu struct ljca_spi_dev { 70caee8e38SWentong Wu struct ljca_client *ljca; 71caee8e38SWentong Wu struct spi_controller *controller; 72caee8e38SWentong Wu struct ljca_spi_info *spi_info; 73caee8e38SWentong Wu u8 speed; 74caee8e38SWentong Wu u8 mode; 75caee8e38SWentong Wu 76caee8e38SWentong Wu u8 obuf[LJCA_SPI_BUF_SIZE]; 77caee8e38SWentong Wu u8 ibuf[LJCA_SPI_BUF_SIZE]; 78caee8e38SWentong Wu }; 79caee8e38SWentong Wu 80caee8e38SWentong Wu static int ljca_spi_read_write(struct ljca_spi_dev *ljca_spi, const u8 *w_data, 81caee8e38SWentong Wu u8 *r_data, int len, int id, int complete, 82caee8e38SWentong Wu int cmd) 83caee8e38SWentong Wu { 84caee8e38SWentong Wu struct ljca_spi_xfer_packet *w_packet = 85caee8e38SWentong Wu (struct ljca_spi_xfer_packet *)ljca_spi->obuf; 86caee8e38SWentong Wu struct ljca_spi_xfer_packet *r_packet = 87caee8e38SWentong Wu (struct ljca_spi_xfer_packet *)ljca_spi->ibuf; 88caee8e38SWentong Wu int ret; 89caee8e38SWentong Wu 90caee8e38SWentong Wu w_packet->indicator = FIELD_PREP(LJCA_SPI_XFER_INDICATOR_ID, id) | 91caee8e38SWentong Wu FIELD_PREP(LJCA_SPI_XFER_INDICATOR_CMPL, complete) | 92caee8e38SWentong Wu FIELD_PREP(LJCA_SPI_XFER_INDICATOR_INDEX, 93caee8e38SWentong Wu ljca_spi->spi_info->id); 94caee8e38SWentong Wu 95caee8e38SWentong Wu if (cmd == LJCA_SPI_READ) { 96caee8e38SWentong Wu w_packet->len = sizeof(u16); 97caee8e38SWentong Wu *(__le16 *)&w_packet->data[0] = cpu_to_le16(len); 98caee8e38SWentong Wu } else { 99caee8e38SWentong Wu w_packet->len = len; 100caee8e38SWentong Wu memcpy(w_packet->data, w_data, len); 101caee8e38SWentong Wu } 102caee8e38SWentong Wu 103caee8e38SWentong Wu ret = ljca_transfer(ljca_spi->ljca, cmd, (u8 *)w_packet, 104caee8e38SWentong Wu struct_size(w_packet, data, w_packet->len), 105caee8e38SWentong Wu (u8 *)r_packet, LJCA_SPI_BUF_SIZE); 106caee8e38SWentong Wu if (ret < 0) 107caee8e38SWentong Wu return ret; 108caee8e38SWentong Wu else if (ret < sizeof(*r_packet) || r_packet->len <= 0) 109caee8e38SWentong Wu return -EIO; 110caee8e38SWentong Wu 111caee8e38SWentong Wu if (r_data) 112caee8e38SWentong Wu memcpy(r_data, r_packet->data, r_packet->len); 113caee8e38SWentong Wu 114caee8e38SWentong Wu return 0; 115caee8e38SWentong Wu } 116caee8e38SWentong Wu 117caee8e38SWentong Wu static int ljca_spi_init(struct ljca_spi_dev *ljca_spi, u8 div, u8 mode) 118caee8e38SWentong Wu { 119caee8e38SWentong Wu struct ljca_spi_init_packet w_packet = {}; 120caee8e38SWentong Wu int ret; 121caee8e38SWentong Wu 122caee8e38SWentong Wu if (ljca_spi->mode == mode && ljca_spi->speed == div) 123caee8e38SWentong Wu return 0; 124caee8e38SWentong Wu 125caee8e38SWentong Wu w_packet.index = ljca_spi->spi_info->id; 126caee8e38SWentong Wu w_packet.speed = div; 127caee8e38SWentong Wu w_packet.mode = FIELD_PREP(LJCA_SPI_CLK_MODE_POLARITY, 128caee8e38SWentong Wu (mode & SPI_CPOL) ? LJCA_SPI_CLOCK_HIGH_POLARITY : 129caee8e38SWentong Wu LJCA_SPI_CLOCK_LOW_POLARITY) | 130caee8e38SWentong Wu FIELD_PREP(LJCA_SPI_CLK_MODE_PHASE, 131caee8e38SWentong Wu (mode & SPI_CPHA) ? LJCA_SPI_CLOCK_SECOND_PHASE : 132caee8e38SWentong Wu LJCA_SPI_CLOCK_FIRST_PHASE); 133caee8e38SWentong Wu 134caee8e38SWentong Wu ret = ljca_transfer(ljca_spi->ljca, LJCA_SPI_INIT, (u8 *)&w_packet, 135caee8e38SWentong Wu sizeof(w_packet), NULL, 0); 136caee8e38SWentong Wu if (ret < 0) 137caee8e38SWentong Wu return ret; 138caee8e38SWentong Wu 139caee8e38SWentong Wu ljca_spi->mode = mode; 140caee8e38SWentong Wu ljca_spi->speed = div; 141caee8e38SWentong Wu 142caee8e38SWentong Wu return 0; 143caee8e38SWentong Wu } 144caee8e38SWentong Wu 145caee8e38SWentong Wu static int ljca_spi_deinit(struct ljca_spi_dev *ljca_spi) 146caee8e38SWentong Wu { 147caee8e38SWentong Wu struct ljca_spi_init_packet w_packet = {}; 148caee8e38SWentong Wu int ret; 149caee8e38SWentong Wu 150caee8e38SWentong Wu w_packet.index = ljca_spi->spi_info->id; 151caee8e38SWentong Wu 152caee8e38SWentong Wu ret = ljca_transfer(ljca_spi->ljca, LJCA_SPI_DEINIT, (u8 *)&w_packet, 153caee8e38SWentong Wu sizeof(w_packet), NULL, 0); 154caee8e38SWentong Wu 155caee8e38SWentong Wu return ret < 0 ? ret : 0; 156caee8e38SWentong Wu } 157caee8e38SWentong Wu 158caee8e38SWentong Wu static inline int ljca_spi_transfer(struct ljca_spi_dev *ljca_spi, 159caee8e38SWentong Wu const u8 *tx_data, u8 *rx_data, u16 len) 160caee8e38SWentong Wu { 161caee8e38SWentong Wu int complete, cur_len; 162caee8e38SWentong Wu int remaining = len; 163caee8e38SWentong Wu int cmd, ret, i; 164caee8e38SWentong Wu int offset = 0; 165caee8e38SWentong Wu 166caee8e38SWentong Wu if (tx_data && rx_data) 167caee8e38SWentong Wu cmd = LJCA_SPI_WRITEREAD; 168caee8e38SWentong Wu else if (tx_data) 169caee8e38SWentong Wu cmd = LJCA_SPI_WRITE; 170caee8e38SWentong Wu else if (rx_data) 171caee8e38SWentong Wu cmd = LJCA_SPI_READ; 172caee8e38SWentong Wu else 173caee8e38SWentong Wu return -EINVAL; 174caee8e38SWentong Wu 175caee8e38SWentong Wu for (i = 0; remaining > 0; i++) { 176caee8e38SWentong Wu cur_len = min_t(unsigned int, remaining, LJCA_SPI_MAX_XFER_SIZE); 177caee8e38SWentong Wu complete = (cur_len == remaining); 178caee8e38SWentong Wu 179caee8e38SWentong Wu ret = ljca_spi_read_write(ljca_spi, 180caee8e38SWentong Wu tx_data ? tx_data + offset : NULL, 181caee8e38SWentong Wu rx_data ? rx_data + offset : NULL, 182caee8e38SWentong Wu cur_len, i, complete, cmd); 183caee8e38SWentong Wu if (ret) 184caee8e38SWentong Wu return ret; 185caee8e38SWentong Wu 186caee8e38SWentong Wu offset += cur_len; 187caee8e38SWentong Wu remaining -= cur_len; 188caee8e38SWentong Wu } 189caee8e38SWentong Wu 190caee8e38SWentong Wu return 0; 191caee8e38SWentong Wu } 192caee8e38SWentong Wu 193caee8e38SWentong Wu static int ljca_spi_transfer_one(struct spi_controller *controller, 194caee8e38SWentong Wu struct spi_device *spi, 195caee8e38SWentong Wu struct spi_transfer *xfer) 196caee8e38SWentong Wu { 197caee8e38SWentong Wu u8 div = DIV_ROUND_UP(controller->max_speed_hz, xfer->speed_hz) / 2 - 1; 198caee8e38SWentong Wu struct ljca_spi_dev *ljca_spi = spi_controller_get_devdata(controller); 199caee8e38SWentong Wu int ret; 200caee8e38SWentong Wu 201caee8e38SWentong Wu div = min_t(u8, LJCA_SPI_BUS_SPEED_MIN, div); 202caee8e38SWentong Wu 203caee8e38SWentong Wu ret = ljca_spi_init(ljca_spi, div, spi->mode); 204caee8e38SWentong Wu if (ret) { 205caee8e38SWentong Wu dev_err(&ljca_spi->ljca->auxdev.dev, 206caee8e38SWentong Wu "cannot initialize transfer ret %d\n", ret); 207caee8e38SWentong Wu return ret; 208caee8e38SWentong Wu } 209caee8e38SWentong Wu 210caee8e38SWentong Wu ret = ljca_spi_transfer(ljca_spi, xfer->tx_buf, xfer->rx_buf, xfer->len); 211caee8e38SWentong Wu if (ret) 212caee8e38SWentong Wu dev_err(&ljca_spi->ljca->auxdev.dev, 213caee8e38SWentong Wu "transfer failed len: %d\n", xfer->len); 214caee8e38SWentong Wu 215caee8e38SWentong Wu return ret; 216caee8e38SWentong Wu } 217caee8e38SWentong Wu 218caee8e38SWentong Wu static int ljca_spi_probe(struct auxiliary_device *auxdev, 219caee8e38SWentong Wu const struct auxiliary_device_id *aux_dev_id) 220caee8e38SWentong Wu { 221caee8e38SWentong Wu struct ljca_client *ljca = auxiliary_dev_to_ljca_client(auxdev); 222caee8e38SWentong Wu struct spi_controller *controller; 223caee8e38SWentong Wu struct ljca_spi_dev *ljca_spi; 224caee8e38SWentong Wu int ret; 225caee8e38SWentong Wu 226*4ac9ed81SYang Yingliang controller = devm_spi_alloc_host(&auxdev->dev, sizeof(*ljca_spi)); 227caee8e38SWentong Wu if (!controller) 228caee8e38SWentong Wu return -ENOMEM; 229caee8e38SWentong Wu 230caee8e38SWentong Wu ljca_spi = spi_controller_get_devdata(controller); 231caee8e38SWentong Wu ljca_spi->ljca = ljca; 232caee8e38SWentong Wu ljca_spi->spi_info = dev_get_platdata(&auxdev->dev); 233caee8e38SWentong Wu ljca_spi->controller = controller; 234caee8e38SWentong Wu 235caee8e38SWentong Wu controller->bus_num = -1; 236caee8e38SWentong Wu controller->mode_bits = SPI_CPHA | SPI_CPOL; 237caee8e38SWentong Wu controller->transfer_one = ljca_spi_transfer_one; 238caee8e38SWentong Wu controller->auto_runtime_pm = false; 239caee8e38SWentong Wu controller->max_speed_hz = LJCA_SPI_BUS_MAX_HZ; 240caee8e38SWentong Wu 241caee8e38SWentong Wu device_set_node(&ljca_spi->controller->dev, dev_fwnode(&auxdev->dev)); 242caee8e38SWentong Wu auxiliary_set_drvdata(auxdev, controller); 243caee8e38SWentong Wu 244caee8e38SWentong Wu ret = spi_register_controller(controller); 245caee8e38SWentong Wu if (ret) 246caee8e38SWentong Wu dev_err(&auxdev->dev, "Failed to register controller\n"); 247caee8e38SWentong Wu 248caee8e38SWentong Wu return ret; 249caee8e38SWentong Wu } 250caee8e38SWentong Wu 251caee8e38SWentong Wu static void ljca_spi_dev_remove(struct auxiliary_device *auxdev) 252caee8e38SWentong Wu { 253caee8e38SWentong Wu struct spi_controller *controller = auxiliary_get_drvdata(auxdev); 254caee8e38SWentong Wu struct ljca_spi_dev *ljca_spi = spi_controller_get_devdata(controller); 255caee8e38SWentong Wu 256caee8e38SWentong Wu spi_unregister_controller(controller); 257caee8e38SWentong Wu ljca_spi_deinit(ljca_spi); 258caee8e38SWentong Wu } 259caee8e38SWentong Wu 260caee8e38SWentong Wu static int ljca_spi_dev_suspend(struct device *dev) 261caee8e38SWentong Wu { 262caee8e38SWentong Wu struct spi_controller *controller = dev_get_drvdata(dev); 263caee8e38SWentong Wu 264caee8e38SWentong Wu return spi_controller_suspend(controller); 265caee8e38SWentong Wu } 266caee8e38SWentong Wu 267caee8e38SWentong Wu static int ljca_spi_dev_resume(struct device *dev) 268caee8e38SWentong Wu { 269caee8e38SWentong Wu struct spi_controller *controller = dev_get_drvdata(dev); 270caee8e38SWentong Wu 271caee8e38SWentong Wu return spi_controller_resume(controller); 272caee8e38SWentong Wu } 273caee8e38SWentong Wu 274caee8e38SWentong Wu static const struct dev_pm_ops ljca_spi_pm = { 275caee8e38SWentong Wu SYSTEM_SLEEP_PM_OPS(ljca_spi_dev_suspend, ljca_spi_dev_resume) 276caee8e38SWentong Wu }; 277caee8e38SWentong Wu 278caee8e38SWentong Wu static const struct auxiliary_device_id ljca_spi_id_table[] = { 279caee8e38SWentong Wu { "usb_ljca.ljca-spi", 0 }, 280caee8e38SWentong Wu { /* sentinel */ } 281caee8e38SWentong Wu }; 282caee8e38SWentong Wu MODULE_DEVICE_TABLE(auxiliary, ljca_spi_id_table); 283caee8e38SWentong Wu 284caee8e38SWentong Wu static struct auxiliary_driver ljca_spi_driver = { 285caee8e38SWentong Wu .driver.pm = &ljca_spi_pm, 286caee8e38SWentong Wu .probe = ljca_spi_probe, 287caee8e38SWentong Wu .remove = ljca_spi_dev_remove, 288caee8e38SWentong Wu .id_table = ljca_spi_id_table, 289caee8e38SWentong Wu }; 290caee8e38SWentong Wu module_auxiliary_driver(ljca_spi_driver); 291caee8e38SWentong Wu 292caee8e38SWentong Wu MODULE_AUTHOR("Wentong Wu <wentong.wu@intel.com>"); 293caee8e38SWentong Wu MODULE_AUTHOR("Zhifeng Wang <zhifeng.wang@intel.com>"); 294caee8e38SWentong Wu MODULE_AUTHOR("Lixu Zhang <lixu.zhang@intel.com>"); 295caee8e38SWentong Wu MODULE_DESCRIPTION("Intel La Jolla Cove Adapter USB-SPI driver"); 296caee8e38SWentong Wu MODULE_LICENSE("GPL"); 297caee8e38SWentong Wu MODULE_IMPORT_NS(LJCA); 298