| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Guenter Roeck | 1350 | 83.85% | 3 | 17.65% |
| Javier Martinez Canillas | 102 | 6.34% | 1 | 5.88% |
| Axel Lin | 69 | 4.29% | 3 | 17.65% |
| Phil Reid | 48 | 2.98% | 2 | 11.76% |
| Vladimir Oltean | 23 | 1.43% | 2 | 11.76% |
| Uwe Kleine-König | 9 | 0.56% | 1 | 5.88% |
| Jingoo Han | 3 | 0.19% | 1 | 5.88% |
| Thomas Gleixner | 2 | 0.12% | 1 | 5.88% |
| Lukas Wunner | 2 | 0.12% | 1 | 5.88% |
| Alexandru Ardelean | 1 | 0.06% | 1 | 5.88% |
| Christophe Jaillet | 1 | 0.06% | 1 | 5.88% |
| Total | 1610 | 17 |
// SPDX-License-Identifier: GPL-2.0-or-later /* * NXP SC18IS602/603 SPI driver * * Copyright (C) Guenter Roeck <linux@roeck-us.net> */ #include <linux/kernel.h> #include <linux/err.h> #include <linux/module.h> #include <linux/spi/spi.h> #include <linux/i2c.h> #include <linux/delay.h> #include <linux/pm_runtime.h> #include <linux/of_device.h> #include <linux/of.h> #include <linux/platform_data/sc18is602.h> #include <linux/gpio/consumer.h> enum chips { sc18is602, sc18is602b, sc18is603 }; #define SC18IS602_BUFSIZ 200 #define SC18IS602_CLOCK 7372000 #define SC18IS602_MODE_CPHA BIT(2) #define SC18IS602_MODE_CPOL BIT(3) #define SC18IS602_MODE_LSB_FIRST BIT(5) #define SC18IS602_MODE_CLOCK_DIV_4 0x0 #define SC18IS602_MODE_CLOCK_DIV_16 0x1 #define SC18IS602_MODE_CLOCK_DIV_64 0x2 #define SC18IS602_MODE_CLOCK_DIV_128 0x3 struct sc18is602 { struct spi_master *master; struct device *dev; u8 ctrl; u32 freq; u32 speed; /* I2C data */ struct i2c_client *client; enum chips id; u8 buffer[SC18IS602_BUFSIZ + 1]; int tlen; /* Data queued for tx in buffer */ int rindex; /* Receive data index in buffer */ struct gpio_desc *reset; }; static int sc18is602_wait_ready(struct sc18is602 *hw, int len) { int i, err; int usecs = 1000000 * len / hw->speed + 1; u8 dummy[1]; for (i = 0; i < 10; i++) { err = i2c_master_recv(hw->client, dummy, 1); if (err >= 0) return 0; usleep_range(usecs, usecs * 2); } return -ETIMEDOUT; } static int sc18is602_txrx(struct sc18is602 *hw, struct spi_message *msg, struct spi_transfer *t, bool do_transfer) { unsigned int len = t->len; int ret; if (hw->tlen == 0) { /* First byte (I2C command) is chip select */ hw->buffer[0] = 1 << msg->spi->chip_select; hw->tlen = 1; hw->rindex = 0; } /* * We can not immediately send data to the chip, since each I2C message * resembles a full SPI message (from CS active to CS inactive). * Enqueue messages up to the first read or until do_transfer is true. */ if (t->tx_buf) { memcpy(&hw->buffer[hw->tlen], t->tx_buf, len); hw->tlen += len; if (t->rx_buf) do_transfer = true; else hw->rindex = hw->tlen - 1; } else if (t->rx_buf) { /* * For receive-only transfers we still need to perform a dummy * write to receive data from the SPI chip. * Read data starts at the end of transmit data (minus 1 to * account for CS). */ hw->rindex = hw->tlen - 1; memset(&hw->buffer[hw->tlen], 0, len); hw->tlen += len; do_transfer = true; } if (do_transfer && hw->tlen > 1) { ret = sc18is602_wait_ready(hw, SC18IS602_BUFSIZ); if (ret < 0) return ret; ret = i2c_master_send(hw->client, hw->buffer, hw->tlen); if (ret < 0) return ret; if (ret != hw->tlen) return -EIO; if (t->rx_buf) { int rlen = hw->rindex + len; ret = sc18is602_wait_ready(hw, hw->tlen); if (ret < 0) return ret; ret = i2c_master_recv(hw->client, hw->buffer, rlen); if (ret < 0) return ret; if (ret != rlen) return -EIO; memcpy(t->rx_buf, &hw->buffer[hw->rindex], len); } hw->tlen = 0; } return len; } static int sc18is602_setup_transfer(struct sc18is602 *hw, u32 hz, u8 mode) { u8 ctrl = 0; int ret; if (mode & SPI_CPHA) ctrl |= SC18IS602_MODE_CPHA; if (mode & SPI_CPOL) ctrl |= SC18IS602_MODE_CPOL; if (mode & SPI_LSB_FIRST) ctrl |= SC18IS602_MODE_LSB_FIRST; /* Find the closest clock speed */ if (hz >= hw->freq / 4) { ctrl |= SC18IS602_MODE_CLOCK_DIV_4; hw->speed = hw->freq / 4; } else if (hz >= hw->freq / 16) { ctrl |= SC18IS602_MODE_CLOCK_DIV_16; hw->speed = hw->freq / 16; } else if (hz >= hw->freq / 64) { ctrl |= SC18IS602_MODE_CLOCK_DIV_64; hw->speed = hw->freq / 64; } else { ctrl |= SC18IS602_MODE_CLOCK_DIV_128; hw->speed = hw->freq / 128; } /* * Don't do anything if the control value did not change. The initial * value of 0xff for hw->ctrl ensures that the correct mode will be set * with the first call to this function. */ if (ctrl == hw->ctrl) return 0; ret = i2c_smbus_write_byte_data(hw->client, 0xf0, ctrl); if (ret < 0) return ret; hw->ctrl = ctrl; return 0; } static int sc18is602_check_transfer(struct spi_device *spi, struct spi_transfer *t, int tlen) { if (t && t->len + tlen > SC18IS602_BUFSIZ + 1) return -EINVAL; return 0; } static int sc18is602_transfer_one(struct spi_master *master, struct spi_message *m) { struct sc18is602 *hw = spi_master_get_devdata(master); struct spi_device *spi = m->spi; struct spi_transfer *t; int status = 0; hw->tlen = 0; list_for_each_entry(t, &m->transfers, transfer_list) { bool do_transfer; status = sc18is602_check_transfer(spi, t, hw->tlen); if (status < 0) break; status = sc18is602_setup_transfer(hw, t->speed_hz, spi->mode); if (status < 0) break; do_transfer = t->cs_change || list_is_last(&t->transfer_list, &m->transfers); if (t->len) { status = sc18is602_txrx(hw, m, t, do_transfer); if (status < 0) break; m->actual_length += status; } status = 0; spi_transfer_delay_exec(t); } m->status = status; spi_finalize_current_message(master); return status; } static size_t sc18is602_max_transfer_size(struct spi_device *spi) { return SC18IS602_BUFSIZ; } static int sc18is602_setup(struct spi_device *spi) { struct sc18is602 *hw = spi_master_get_devdata(spi->master); /* SC18IS602 does not support CS2 */ if (hw->id == sc18is602 && spi->chip_select == 2) return -ENXIO; return 0; } static int sc18is602_probe(struct i2c_client *client) { const struct i2c_device_id *id = i2c_client_get_device_id(client); struct device *dev = &client->dev; struct device_node *np = dev->of_node; struct sc18is602_platform_data *pdata = dev_get_platdata(dev); struct sc18is602 *hw; struct spi_master *master; if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) return -EINVAL; master = devm_spi_alloc_master(dev, sizeof(struct sc18is602)); if (!master) return -ENOMEM; hw = spi_master_get_devdata(master); i2c_set_clientdata(client, hw); /* assert reset and then release */ hw->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); if (IS_ERR(hw->reset)) return PTR_ERR(hw->reset); gpiod_set_value_cansleep(hw->reset, 0); hw->master = master; hw->client = client; hw->dev = dev; hw->ctrl = 0xff; if (client->dev.of_node) hw->id = (enum chips)of_device_get_match_data(&client->dev); else hw->id = id->driver_data; switch (hw->id) { case sc18is602: case sc18is602b: master->num_chipselect = 4; hw->freq = SC18IS602_CLOCK; break; case sc18is603: master->num_chipselect = 2; if (pdata) { hw->freq = pdata->clock_frequency; } else { const __be32 *val; int len; val = of_get_property(np, "clock-frequency", &len); if (val && len >= sizeof(__be32)) hw->freq = be32_to_cpup(val); } if (!hw->freq) hw->freq = SC18IS602_CLOCK; break; } master->bus_num = np ? -1 : client->adapter->nr; master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_LSB_FIRST; master->bits_per_word_mask = SPI_BPW_MASK(8); master->setup = sc18is602_setup; master->transfer_one_message = sc18is602_transfer_one; master->max_transfer_size = sc18is602_max_transfer_size; master->max_message_size = sc18is602_max_transfer_size; master->dev.of_node = np; master->min_speed_hz = hw->freq / 128; master->max_speed_hz = hw->freq / 4; return devm_spi_register_master(dev, master); } static const struct i2c_device_id sc18is602_id[] = { { "sc18is602", sc18is602 }, { "sc18is602b", sc18is602b }, { "sc18is603", sc18is603 }, { } }; MODULE_DEVICE_TABLE(i2c, sc18is602_id); static const struct of_device_id sc18is602_of_match[] = { { .compatible = "nxp,sc18is602", .data = (void *)sc18is602 }, { .compatible = "nxp,sc18is602b", .data = (void *)sc18is602b }, { .compatible = "nxp,sc18is603", .data = (void *)sc18is603 }, { }, }; MODULE_DEVICE_TABLE(of, sc18is602_of_match); static struct i2c_driver sc18is602_driver = { .driver = { .name = "sc18is602", .of_match_table = of_match_ptr(sc18is602_of_match), }, .probe_new = sc18is602_probe, .id_table = sc18is602_id, }; module_i2c_driver(sc18is602_driver); MODULE_DESCRIPTION("SC18IS602/603 SPI Master Driver"); MODULE_AUTHOR("Guenter Roeck"); MODULE_LICENSE("GPL");
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