1 /* 2 * Samsung LSI S5C73M3 8M pixel camera driver 3 * 4 * Copyright (C) 2012, Samsung Electronics, Co., Ltd. 5 * Sylwester Nawrocki <s.nawrocki@samsung.com> 6 * Andrzej Hajda <a.hajda@samsung.com> 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * version 2 as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 */ 17 18 #include <linux/sizes.h> 19 #include <linux/delay.h> 20 #include <linux/init.h> 21 #include <linux/media.h> 22 #include <linux/module.h> 23 #include <linux/slab.h> 24 #include <linux/spi/spi.h> 25 26 #include "s5c73m3.h" 27 28 #define S5C73M3_SPI_DRV_NAME "S5C73M3-SPI" 29 30 static const struct of_device_id s5c73m3_spi_ids[] = { 31 { .compatible = "samsung,s5c73m3" }, 32 { } 33 }; 34 MODULE_DEVICE_TABLE(of, s5c73m3_spi_ids); 35 36 enum spi_direction { 37 SPI_DIR_RX, 38 SPI_DIR_TX 39 }; 40 41 static int spi_xmit(struct spi_device *spi_dev, void *addr, const int len, 42 enum spi_direction dir) 43 { 44 struct spi_message msg; 45 int r; 46 struct spi_transfer xfer = { 47 .len = len, 48 }; 49 50 if (dir == SPI_DIR_TX) 51 xfer.tx_buf = addr; 52 else 53 xfer.rx_buf = addr; 54 55 if (spi_dev == NULL) { 56 pr_err("SPI device is uninitialized\n"); 57 return -ENODEV; 58 } 59 60 spi_message_init(&msg); 61 spi_message_add_tail(&xfer, &msg); 62 63 r = spi_sync(spi_dev, &msg); 64 if (r < 0) 65 dev_err(&spi_dev->dev, "%s spi_sync failed %d\n", __func__, r); 66 67 return r; 68 } 69 70 int s5c73m3_spi_write(struct s5c73m3 *state, const void *addr, 71 const unsigned int len, const unsigned int tx_size) 72 { 73 struct spi_device *spi_dev = state->spi_dev; 74 u32 count = len / tx_size; 75 u32 extra = len % tx_size; 76 unsigned int i, j = 0; 77 u8 padding[32]; 78 int r = 0; 79 80 memset(padding, 0, sizeof(padding)); 81 82 for (i = 0; i < count; i++) { 83 r = spi_xmit(spi_dev, (void *)addr + j, tx_size, SPI_DIR_TX); 84 if (r < 0) 85 return r; 86 j += tx_size; 87 } 88 89 if (extra > 0) { 90 r = spi_xmit(spi_dev, (void *)addr + j, extra, SPI_DIR_TX); 91 if (r < 0) 92 return r; 93 } 94 95 return spi_xmit(spi_dev, padding, sizeof(padding), SPI_DIR_TX); 96 } 97 98 int s5c73m3_spi_read(struct s5c73m3 *state, void *addr, 99 const unsigned int len, const unsigned int tx_size) 100 { 101 struct spi_device *spi_dev = state->spi_dev; 102 u32 count = len / tx_size; 103 u32 extra = len % tx_size; 104 unsigned int i, j = 0; 105 int r = 0; 106 107 for (i = 0; i < count; i++) { 108 r = spi_xmit(spi_dev, addr + j, tx_size, SPI_DIR_RX); 109 if (r < 0) 110 return r; 111 j += tx_size; 112 } 113 114 if (extra > 0) 115 return spi_xmit(spi_dev, addr + j, extra, SPI_DIR_RX); 116 117 return 0; 118 } 119 120 static int s5c73m3_spi_probe(struct spi_device *spi) 121 { 122 int r; 123 struct s5c73m3 *state = container_of(spi->dev.driver, struct s5c73m3, 124 spidrv.driver); 125 spi->bits_per_word = 32; 126 127 r = spi_setup(spi); 128 if (r < 0) { 129 dev_err(&spi->dev, "spi_setup() failed\n"); 130 return r; 131 } 132 133 mutex_lock(&state->lock); 134 state->spi_dev = spi; 135 mutex_unlock(&state->lock); 136 137 v4l2_info(&state->sensor_sd, "S5C73M3 SPI probed successfully\n"); 138 return 0; 139 } 140 141 static int s5c73m3_spi_remove(struct spi_device *spi) 142 { 143 return 0; 144 } 145 146 int s5c73m3_register_spi_driver(struct s5c73m3 *state) 147 { 148 struct spi_driver *spidrv = &state->spidrv; 149 150 spidrv->remove = s5c73m3_spi_remove; 151 spidrv->probe = s5c73m3_spi_probe; 152 spidrv->driver.name = S5C73M3_SPI_DRV_NAME; 153 spidrv->driver.of_match_table = s5c73m3_spi_ids; 154 155 return spi_register_driver(spidrv); 156 } 157 158 void s5c73m3_unregister_spi_driver(struct s5c73m3 *state) 159 { 160 spi_unregister_driver(&state->spidrv); 161 } 162