1 /* 2 * Freescale SPI/eSPI controller driver library. 3 * 4 * Maintainer: Kumar Gala 5 * 6 * Copyright (C) 2006 Polycom, Inc. 7 * 8 * CPM SPI and QE buffer descriptors mode support: 9 * Copyright (c) 2009 MontaVista Software, Inc. 10 * Author: Anton Vorontsov <avorontsov@ru.mvista.com> 11 * 12 * Copyright 2010 Freescale Semiconductor, Inc. 13 * 14 * This program is free software; you can redistribute it and/or modify it 15 * under the terms of the GNU General Public License as published by the 16 * Free Software Foundation; either version 2 of the License, or (at your 17 * option) any later version. 18 */ 19 #include <linux/kernel.h> 20 #include <linux/interrupt.h> 21 #include <linux/fsl_devices.h> 22 #include <linux/dma-mapping.h> 23 #include <linux/mm.h> 24 #include <linux/of_platform.h> 25 #include <linux/spi/spi.h> 26 #include <sysdev/fsl_soc.h> 27 28 #include "spi-fsl-lib.h" 29 30 #define MPC8XXX_SPI_RX_BUF(type) \ 31 void mpc8xxx_spi_rx_buf_##type(u32 data, struct mpc8xxx_spi *mpc8xxx_spi) \ 32 { \ 33 type *rx = mpc8xxx_spi->rx; \ 34 *rx++ = (type)(data >> mpc8xxx_spi->rx_shift); \ 35 mpc8xxx_spi->rx = rx; \ 36 } 37 38 #define MPC8XXX_SPI_TX_BUF(type) \ 39 u32 mpc8xxx_spi_tx_buf_##type(struct mpc8xxx_spi *mpc8xxx_spi) \ 40 { \ 41 u32 data; \ 42 const type *tx = mpc8xxx_spi->tx; \ 43 if (!tx) \ 44 return 0; \ 45 data = *tx++ << mpc8xxx_spi->tx_shift; \ 46 mpc8xxx_spi->tx = tx; \ 47 return data; \ 48 } 49 50 MPC8XXX_SPI_RX_BUF(u8) 51 MPC8XXX_SPI_RX_BUF(u16) 52 MPC8XXX_SPI_RX_BUF(u32) 53 MPC8XXX_SPI_TX_BUF(u8) 54 MPC8XXX_SPI_TX_BUF(u16) 55 MPC8XXX_SPI_TX_BUF(u32) 56 57 struct mpc8xxx_spi_probe_info *to_of_pinfo(struct fsl_spi_platform_data *pdata) 58 { 59 return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata); 60 } 61 62 void mpc8xxx_spi_work(struct work_struct *work) 63 { 64 struct mpc8xxx_spi *mpc8xxx_spi = container_of(work, struct mpc8xxx_spi, 65 work); 66 67 spin_lock_irq(&mpc8xxx_spi->lock); 68 while (!list_empty(&mpc8xxx_spi->queue)) { 69 struct spi_message *m = container_of(mpc8xxx_spi->queue.next, 70 struct spi_message, queue); 71 72 list_del_init(&m->queue); 73 spin_unlock_irq(&mpc8xxx_spi->lock); 74 75 if (mpc8xxx_spi->spi_do_one_msg) 76 mpc8xxx_spi->spi_do_one_msg(m); 77 78 spin_lock_irq(&mpc8xxx_spi->lock); 79 } 80 spin_unlock_irq(&mpc8xxx_spi->lock); 81 } 82 83 int mpc8xxx_spi_transfer(struct spi_device *spi, 84 struct spi_message *m) 85 { 86 struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master); 87 unsigned long flags; 88 89 m->actual_length = 0; 90 m->status = -EINPROGRESS; 91 92 spin_lock_irqsave(&mpc8xxx_spi->lock, flags); 93 list_add_tail(&m->queue, &mpc8xxx_spi->queue); 94 queue_work(mpc8xxx_spi->workqueue, &mpc8xxx_spi->work); 95 spin_unlock_irqrestore(&mpc8xxx_spi->lock, flags); 96 97 return 0; 98 } 99 100 void mpc8xxx_spi_cleanup(struct spi_device *spi) 101 { 102 kfree(spi->controller_state); 103 } 104 105 const char *mpc8xxx_spi_strmode(unsigned int flags) 106 { 107 if (flags & SPI_QE_CPU_MODE) { 108 return "QE CPU"; 109 } else if (flags & SPI_CPM_MODE) { 110 if (flags & SPI_QE) 111 return "QE"; 112 else if (flags & SPI_CPM2) 113 return "CPM2"; 114 else 115 return "CPM1"; 116 } 117 return "CPU"; 118 } 119 120 int mpc8xxx_spi_probe(struct device *dev, struct resource *mem, 121 unsigned int irq) 122 { 123 struct fsl_spi_platform_data *pdata = dev->platform_data; 124 struct spi_master *master; 125 struct mpc8xxx_spi *mpc8xxx_spi; 126 int ret = 0; 127 128 master = dev_get_drvdata(dev); 129 130 /* the spi->mode bits understood by this driver: */ 131 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH 132 | SPI_LSB_FIRST | SPI_LOOP; 133 134 master->transfer = mpc8xxx_spi_transfer; 135 master->cleanup = mpc8xxx_spi_cleanup; 136 master->dev.of_node = dev->of_node; 137 138 mpc8xxx_spi = spi_master_get_devdata(master); 139 mpc8xxx_spi->dev = dev; 140 mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8; 141 mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8; 142 mpc8xxx_spi->flags = pdata->flags; 143 mpc8xxx_spi->spibrg = pdata->sysclk; 144 mpc8xxx_spi->irq = irq; 145 146 mpc8xxx_spi->rx_shift = 0; 147 mpc8xxx_spi->tx_shift = 0; 148 149 init_completion(&mpc8xxx_spi->done); 150 151 master->bus_num = pdata->bus_num; 152 master->num_chipselect = pdata->max_chipselect; 153 154 spin_lock_init(&mpc8xxx_spi->lock); 155 init_completion(&mpc8xxx_spi->done); 156 INIT_WORK(&mpc8xxx_spi->work, mpc8xxx_spi_work); 157 INIT_LIST_HEAD(&mpc8xxx_spi->queue); 158 159 mpc8xxx_spi->workqueue = create_singlethread_workqueue( 160 dev_name(master->dev.parent)); 161 if (mpc8xxx_spi->workqueue == NULL) { 162 ret = -EBUSY; 163 goto err; 164 } 165 166 return 0; 167 168 err: 169 return ret; 170 } 171 172 int mpc8xxx_spi_remove(struct device *dev) 173 { 174 struct mpc8xxx_spi *mpc8xxx_spi; 175 struct spi_master *master; 176 177 master = dev_get_drvdata(dev); 178 mpc8xxx_spi = spi_master_get_devdata(master); 179 180 flush_workqueue(mpc8xxx_spi->workqueue); 181 destroy_workqueue(mpc8xxx_spi->workqueue); 182 spi_unregister_master(master); 183 184 free_irq(mpc8xxx_spi->irq, mpc8xxx_spi); 185 186 if (mpc8xxx_spi->spi_remove) 187 mpc8xxx_spi->spi_remove(mpc8xxx_spi); 188 189 return 0; 190 } 191 192 int of_mpc8xxx_spi_probe(struct platform_device *ofdev) 193 { 194 struct device *dev = &ofdev->dev; 195 struct device_node *np = ofdev->dev.of_node; 196 struct mpc8xxx_spi_probe_info *pinfo; 197 struct fsl_spi_platform_data *pdata; 198 const void *prop; 199 int ret = -ENOMEM; 200 201 pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL); 202 if (!pinfo) 203 return -ENOMEM; 204 205 pdata = &pinfo->pdata; 206 dev->platform_data = pdata; 207 208 /* Allocate bus num dynamically. */ 209 pdata->bus_num = -1; 210 211 /* SPI controller is either clocked from QE or SoC clock. */ 212 pdata->sysclk = get_brgfreq(); 213 if (pdata->sysclk == -1) { 214 pdata->sysclk = fsl_get_sys_freq(); 215 if (pdata->sysclk == -1) { 216 ret = -ENODEV; 217 goto err; 218 } 219 } 220 221 prop = of_get_property(np, "mode", NULL); 222 if (prop && !strcmp(prop, "cpu-qe")) 223 pdata->flags = SPI_QE_CPU_MODE; 224 else if (prop && !strcmp(prop, "qe")) 225 pdata->flags = SPI_CPM_MODE | SPI_QE; 226 else if (of_device_is_compatible(np, "fsl,cpm2-spi")) 227 pdata->flags = SPI_CPM_MODE | SPI_CPM2; 228 else if (of_device_is_compatible(np, "fsl,cpm1-spi")) 229 pdata->flags = SPI_CPM_MODE | SPI_CPM1; 230 231 return 0; 232 233 err: 234 kfree(pinfo); 235 return ret; 236 } 237