1 /* 2 * netup_unidvb_spi.c 3 * 4 * Internal SPI driver for NetUP Universal Dual DVB-CI 5 * 6 * Copyright (C) 2014 NetUP Inc. 7 * Copyright (C) 2014 Sergey Kozlov <serjk@netup.ru> 8 * Copyright (C) 2014 Abylay Ospan <aospan@netup.ru> 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 */ 20 21 #include "netup_unidvb.h" 22 #include <linux/spi/spi.h> 23 #include <linux/spi/flash.h> 24 #include <linux/mtd/partitions.h> 25 #include <mtd/mtd-abi.h> 26 27 #define NETUP_SPI_CTRL_IRQ 0x1000 28 #define NETUP_SPI_CTRL_IMASK 0x2000 29 #define NETUP_SPI_CTRL_START 0x8000 30 #define NETUP_SPI_CTRL_LAST_CS 0x4000 31 32 #define NETUP_SPI_TIMEOUT 6000 33 34 enum netup_spi_state { 35 SPI_STATE_START, 36 SPI_STATE_DONE, 37 }; 38 39 struct netup_spi_regs { 40 __u8 data[1024]; 41 __le16 control_stat; 42 __le16 clock_divider; 43 } __packed __aligned(1); 44 45 struct netup_spi { 46 struct device *dev; 47 struct spi_master *master; 48 struct netup_spi_regs __iomem *regs; 49 u8 __iomem *mmio; 50 spinlock_t lock; 51 wait_queue_head_t waitq; 52 enum netup_spi_state state; 53 }; 54 55 static char netup_spi_name[64] = "fpga"; 56 57 static struct mtd_partition netup_spi_flash_partitions = { 58 .name = netup_spi_name, 59 .size = 0x1000000, /* 16MB */ 60 .offset = 0, 61 .mask_flags = MTD_CAP_ROM 62 }; 63 64 static struct flash_platform_data spi_flash_data = { 65 .name = "netup0_m25p128", 66 .parts = &netup_spi_flash_partitions, 67 .nr_parts = 1, 68 }; 69 70 static struct spi_board_info netup_spi_board = { 71 .modalias = "m25p128", 72 .max_speed_hz = 11000000, 73 .chip_select = 0, 74 .mode = SPI_MODE_0, 75 .platform_data = &spi_flash_data, 76 }; 77 78 irqreturn_t netup_spi_interrupt(struct netup_spi *spi) 79 { 80 u16 reg; 81 unsigned long flags; 82 83 if (!spi) 84 return IRQ_NONE; 85 86 spin_lock_irqsave(&spi->lock, flags); 87 reg = readw(&spi->regs->control_stat); 88 if (!(reg & NETUP_SPI_CTRL_IRQ)) { 89 spin_unlock_irqrestore(&spi->lock, flags); 90 dev_dbg(&spi->master->dev, 91 "%s(): not mine interrupt\n", __func__); 92 return IRQ_NONE; 93 } 94 writew(reg | NETUP_SPI_CTRL_IRQ, &spi->regs->control_stat); 95 reg = readw(&spi->regs->control_stat); 96 writew(reg & ~NETUP_SPI_CTRL_IMASK, &spi->regs->control_stat); 97 spi->state = SPI_STATE_DONE; 98 wake_up(&spi->waitq); 99 spin_unlock_irqrestore(&spi->lock, flags); 100 dev_dbg(&spi->master->dev, 101 "%s(): SPI interrupt handled\n", __func__); 102 return IRQ_HANDLED; 103 } 104 105 static int netup_spi_transfer(struct spi_master *master, 106 struct spi_message *msg) 107 { 108 struct netup_spi *spi = spi_master_get_devdata(master); 109 struct spi_transfer *t; 110 int result = 0; 111 u32 tr_size; 112 113 /* reset CS */ 114 writew(NETUP_SPI_CTRL_LAST_CS, &spi->regs->control_stat); 115 writew(0, &spi->regs->control_stat); 116 list_for_each_entry(t, &msg->transfers, transfer_list) { 117 tr_size = t->len; 118 while (tr_size) { 119 u32 frag_offset = t->len - tr_size; 120 u32 frag_size = (tr_size > sizeof(spi->regs->data)) ? 121 sizeof(spi->regs->data) : tr_size; 122 int frag_last = 0; 123 124 if (list_is_last(&t->transfer_list, 125 &msg->transfers) && 126 frag_offset + frag_size == t->len) { 127 frag_last = 1; 128 } 129 if (t->tx_buf) { 130 memcpy_toio(spi->regs->data, 131 t->tx_buf + frag_offset, 132 frag_size); 133 } else { 134 memset_io(spi->regs->data, 135 0, frag_size); 136 } 137 spi->state = SPI_STATE_START; 138 writew((frag_size & 0x3ff) | 139 NETUP_SPI_CTRL_IMASK | 140 NETUP_SPI_CTRL_START | 141 (frag_last ? NETUP_SPI_CTRL_LAST_CS : 0), 142 &spi->regs->control_stat); 143 dev_dbg(&spi->master->dev, 144 "%s(): control_stat 0x%04x\n", 145 __func__, readw(&spi->regs->control_stat)); 146 wait_event_timeout(spi->waitq, 147 spi->state != SPI_STATE_START, 148 msecs_to_jiffies(NETUP_SPI_TIMEOUT)); 149 if (spi->state == SPI_STATE_DONE) { 150 if (t->rx_buf) { 151 memcpy_fromio(t->rx_buf + frag_offset, 152 spi->regs->data, frag_size); 153 } 154 } else { 155 if (spi->state == SPI_STATE_START) { 156 dev_dbg(&spi->master->dev, 157 "%s(): transfer timeout\n", 158 __func__); 159 } else { 160 dev_dbg(&spi->master->dev, 161 "%s(): invalid state %d\n", 162 __func__, spi->state); 163 } 164 result = -EIO; 165 goto done; 166 } 167 tr_size -= frag_size; 168 msg->actual_length += frag_size; 169 } 170 } 171 done: 172 msg->status = result; 173 spi_finalize_current_message(master); 174 return result; 175 } 176 177 static int netup_spi_setup(struct spi_device *spi) 178 { 179 return 0; 180 } 181 182 int netup_spi_init(struct netup_unidvb_dev *ndev) 183 { 184 struct spi_master *master; 185 struct netup_spi *nspi; 186 187 master = spi_alloc_master(&ndev->pci_dev->dev, 188 sizeof(struct netup_spi)); 189 if (!master) { 190 dev_err(&ndev->pci_dev->dev, 191 "%s(): unable to alloc SPI master\n", __func__); 192 return -EINVAL; 193 } 194 nspi = spi_master_get_devdata(master); 195 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST; 196 master->bus_num = -1; 197 master->num_chipselect = 1; 198 master->transfer_one_message = netup_spi_transfer; 199 master->setup = netup_spi_setup; 200 spin_lock_init(&nspi->lock); 201 init_waitqueue_head(&nspi->waitq); 202 nspi->master = master; 203 nspi->regs = (struct netup_spi_regs __iomem *)(ndev->bmmio0 + 0x4000); 204 writew(2, &nspi->regs->clock_divider); 205 writew(NETUP_UNIDVB_IRQ_SPI, ndev->bmmio0 + REG_IMASK_SET); 206 ndev->spi = nspi; 207 if (spi_register_master(master)) { 208 ndev->spi = NULL; 209 dev_err(&ndev->pci_dev->dev, 210 "%s(): unable to register SPI bus\n", __func__); 211 return -EINVAL; 212 } 213 snprintf(netup_spi_name, 214 sizeof(netup_spi_name), 215 "fpga_%02x:%02x.%01x", 216 ndev->pci_bus, 217 ndev->pci_slot, 218 ndev->pci_func); 219 if (!spi_new_device(master, &netup_spi_board)) { 220 ndev->spi = NULL; 221 dev_err(&ndev->pci_dev->dev, 222 "%s(): unable to create SPI device\n", __func__); 223 return -EINVAL; 224 } 225 dev_dbg(&ndev->pci_dev->dev, "%s(): SPI init OK\n", __func__); 226 return 0; 227 } 228 229 void netup_spi_release(struct netup_unidvb_dev *ndev) 230 { 231 u16 reg; 232 unsigned long flags; 233 struct netup_spi *spi = ndev->spi; 234 235 if (!spi) 236 return; 237 238 spin_lock_irqsave(&spi->lock, flags); 239 reg = readw(&spi->regs->control_stat); 240 writew(reg | NETUP_SPI_CTRL_IRQ, &spi->regs->control_stat); 241 reg = readw(&spi->regs->control_stat); 242 writew(reg & ~NETUP_SPI_CTRL_IMASK, &spi->regs->control_stat); 243 spin_unlock_irqrestore(&spi->lock, flags); 244 spi_unregister_master(spi->master); 245 ndev->spi = NULL; 246 } 247 248 249