1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Samsung LSI S5C73M3 8M pixel camera driver 4 * 5 * Copyright (C) 2012, Samsung Electronics, Co., Ltd. 6 * Sylwester Nawrocki <s.nawrocki@samsung.com> 7 * Andrzej Hajda <a.hajda@samsung.com> 8 */ 9 10 #include <linux/sizes.h> 11 #include <linux/delay.h> 12 #include <linux/init.h> 13 #include <linux/media.h> 14 #include <linux/module.h> 15 #include <linux/slab.h> 16 #include <linux/spi/spi.h> 17 18 #include "s5c73m3.h" 19 20 #define S5C73M3_SPI_DRV_NAME "S5C73M3-SPI" 21 22 static const struct of_device_id s5c73m3_spi_ids[] = { 23 { .compatible = "samsung,s5c73m3" }, 24 { } 25 }; 26 MODULE_DEVICE_TABLE(of, s5c73m3_spi_ids); 27 28 enum spi_direction { 29 SPI_DIR_RX, 30 SPI_DIR_TX 31 }; 32 33 static int spi_xmit(struct spi_device *spi_dev, void *addr, const int len, 34 enum spi_direction dir) 35 { 36 struct spi_message msg; 37 int r; 38 struct spi_transfer xfer = { 39 .len = len, 40 }; 41 42 if (dir == SPI_DIR_TX) 43 xfer.tx_buf = addr; 44 else 45 xfer.rx_buf = addr; 46 47 if (spi_dev == NULL) { 48 pr_err("SPI device is uninitialized\n"); 49 return -ENODEV; 50 } 51 52 spi_message_init(&msg); 53 spi_message_add_tail(&xfer, &msg); 54 55 r = spi_sync(spi_dev, &msg); 56 if (r < 0) 57 dev_err(&spi_dev->dev, "%s spi_sync failed %d\n", __func__, r); 58 59 return r; 60 } 61 62 int s5c73m3_spi_write(struct s5c73m3 *state, const void *addr, 63 const unsigned int len, const unsigned int tx_size) 64 { 65 struct spi_device *spi_dev = state->spi_dev; 66 u32 count = len / tx_size; 67 u32 extra = len % tx_size; 68 unsigned int i, j = 0; 69 u8 padding[32]; 70 int r = 0; 71 72 memset(padding, 0, sizeof(padding)); 73 74 for (i = 0; i < count; i++) { 75 r = spi_xmit(spi_dev, (void *)addr + j, tx_size, SPI_DIR_TX); 76 if (r < 0) 77 return r; 78 j += tx_size; 79 } 80 81 if (extra > 0) { 82 r = spi_xmit(spi_dev, (void *)addr + j, extra, SPI_DIR_TX); 83 if (r < 0) 84 return r; 85 } 86 87 return spi_xmit(spi_dev, padding, sizeof(padding), SPI_DIR_TX); 88 } 89 90 int s5c73m3_spi_read(struct s5c73m3 *state, void *addr, 91 const unsigned int len, const unsigned int tx_size) 92 { 93 struct spi_device *spi_dev = state->spi_dev; 94 u32 count = len / tx_size; 95 u32 extra = len % tx_size; 96 unsigned int i, j = 0; 97 int r = 0; 98 99 for (i = 0; i < count; i++) { 100 r = spi_xmit(spi_dev, addr + j, tx_size, SPI_DIR_RX); 101 if (r < 0) 102 return r; 103 j += tx_size; 104 } 105 106 if (extra > 0) 107 return spi_xmit(spi_dev, addr + j, extra, SPI_DIR_RX); 108 109 return 0; 110 } 111 112 static int s5c73m3_spi_probe(struct spi_device *spi) 113 { 114 int r; 115 struct s5c73m3 *state = container_of(spi->dev.driver, struct s5c73m3, 116 spidrv.driver); 117 spi->bits_per_word = 32; 118 119 r = spi_setup(spi); 120 if (r < 0) { 121 dev_err(&spi->dev, "spi_setup() failed\n"); 122 return r; 123 } 124 125 mutex_lock(&state->lock); 126 state->spi_dev = spi; 127 mutex_unlock(&state->lock); 128 129 v4l2_info(&state->sensor_sd, "S5C73M3 SPI probed successfully\n"); 130 return 0; 131 } 132 133 int s5c73m3_register_spi_driver(struct s5c73m3 *state) 134 { 135 struct spi_driver *spidrv = &state->spidrv; 136 137 spidrv->probe = s5c73m3_spi_probe; 138 spidrv->driver.name = S5C73M3_SPI_DRV_NAME; 139 spidrv->driver.of_match_table = s5c73m3_spi_ids; 140 141 return spi_register_driver(spidrv); 142 } 143 144 void s5c73m3_unregister_spi_driver(struct s5c73m3 *state) 145 { 146 spi_unregister_driver(&state->spidrv); 147 } 148