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 #ifdef CONFIG_FSL_SOC 27 #include <sysdev/fsl_soc.h> 28 #endif 29 30 #include "spi-fsl-lib.h" 31 32 #define MPC8XXX_SPI_RX_BUF(type) \ 33 void mpc8xxx_spi_rx_buf_##type(u32 data, struct mpc8xxx_spi *mpc8xxx_spi) \ 34 { \ 35 type *rx = mpc8xxx_spi->rx; \ 36 *rx++ = (type)(data >> mpc8xxx_spi->rx_shift); \ 37 mpc8xxx_spi->rx = rx; \ 38 } 39 40 #define MPC8XXX_SPI_TX_BUF(type) \ 41 u32 mpc8xxx_spi_tx_buf_##type(struct mpc8xxx_spi *mpc8xxx_spi) \ 42 { \ 43 u32 data; \ 44 const type *tx = mpc8xxx_spi->tx; \ 45 if (!tx) \ 46 return 0; \ 47 data = *tx++ << mpc8xxx_spi->tx_shift; \ 48 mpc8xxx_spi->tx = tx; \ 49 return data; \ 50 } 51 52 MPC8XXX_SPI_RX_BUF(u8) 53 MPC8XXX_SPI_RX_BUF(u16) 54 MPC8XXX_SPI_RX_BUF(u32) 55 MPC8XXX_SPI_TX_BUF(u8) 56 MPC8XXX_SPI_TX_BUF(u16) 57 MPC8XXX_SPI_TX_BUF(u32) 58 59 struct mpc8xxx_spi_probe_info *to_of_pinfo(struct fsl_spi_platform_data *pdata) 60 { 61 return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata); 62 } 63 64 static void mpc8xxx_spi_work(struct work_struct *work) 65 { 66 struct mpc8xxx_spi *mpc8xxx_spi = container_of(work, struct mpc8xxx_spi, 67 work); 68 69 spin_lock_irq(&mpc8xxx_spi->lock); 70 while (!list_empty(&mpc8xxx_spi->queue)) { 71 struct spi_message *m = container_of(mpc8xxx_spi->queue.next, 72 struct spi_message, queue); 73 74 list_del_init(&m->queue); 75 spin_unlock_irq(&mpc8xxx_spi->lock); 76 77 if (mpc8xxx_spi->spi_do_one_msg) 78 mpc8xxx_spi->spi_do_one_msg(m); 79 80 spin_lock_irq(&mpc8xxx_spi->lock); 81 } 82 spin_unlock_irq(&mpc8xxx_spi->lock); 83 } 84 85 int mpc8xxx_spi_transfer(struct spi_device *spi, 86 struct spi_message *m) 87 { 88 struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master); 89 unsigned long flags; 90 91 m->actual_length = 0; 92 m->status = -EINPROGRESS; 93 94 spin_lock_irqsave(&mpc8xxx_spi->lock, flags); 95 list_add_tail(&m->queue, &mpc8xxx_spi->queue); 96 queue_work(mpc8xxx_spi->workqueue, &mpc8xxx_spi->work); 97 spin_unlock_irqrestore(&mpc8xxx_spi->lock, flags); 98 99 return 0; 100 } 101 102 const char *mpc8xxx_spi_strmode(unsigned int flags) 103 { 104 if (flags & SPI_QE_CPU_MODE) { 105 return "QE CPU"; 106 } else if (flags & SPI_CPM_MODE) { 107 if (flags & SPI_QE) 108 return "QE"; 109 else if (flags & SPI_CPM2) 110 return "CPM2"; 111 else 112 return "CPM1"; 113 } 114 return "CPU"; 115 } 116 117 int mpc8xxx_spi_probe(struct device *dev, struct resource *mem, 118 unsigned int irq) 119 { 120 struct fsl_spi_platform_data *pdata = dev_get_platdata(dev); 121 struct spi_master *master; 122 struct mpc8xxx_spi *mpc8xxx_spi; 123 int ret = 0; 124 125 master = dev_get_drvdata(dev); 126 127 /* the spi->mode bits understood by this driver: */ 128 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH 129 | SPI_LSB_FIRST | SPI_LOOP; 130 131 master->transfer = mpc8xxx_spi_transfer; 132 master->dev.of_node = dev->of_node; 133 134 mpc8xxx_spi = spi_master_get_devdata(master); 135 mpc8xxx_spi->dev = dev; 136 mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8; 137 mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8; 138 mpc8xxx_spi->flags = pdata->flags; 139 mpc8xxx_spi->spibrg = pdata->sysclk; 140 mpc8xxx_spi->irq = irq; 141 142 mpc8xxx_spi->rx_shift = 0; 143 mpc8xxx_spi->tx_shift = 0; 144 145 init_completion(&mpc8xxx_spi->done); 146 147 master->bus_num = pdata->bus_num; 148 master->num_chipselect = pdata->max_chipselect; 149 150 spin_lock_init(&mpc8xxx_spi->lock); 151 init_completion(&mpc8xxx_spi->done); 152 INIT_WORK(&mpc8xxx_spi->work, mpc8xxx_spi_work); 153 INIT_LIST_HEAD(&mpc8xxx_spi->queue); 154 155 mpc8xxx_spi->workqueue = create_singlethread_workqueue( 156 dev_name(master->dev.parent)); 157 if (mpc8xxx_spi->workqueue == NULL) { 158 ret = -EBUSY; 159 goto err; 160 } 161 162 return 0; 163 164 err: 165 return ret; 166 } 167 168 int mpc8xxx_spi_remove(struct device *dev) 169 { 170 struct mpc8xxx_spi *mpc8xxx_spi; 171 struct spi_master *master; 172 173 master = dev_get_drvdata(dev); 174 mpc8xxx_spi = spi_master_get_devdata(master); 175 176 flush_workqueue(mpc8xxx_spi->workqueue); 177 destroy_workqueue(mpc8xxx_spi->workqueue); 178 spi_unregister_master(master); 179 180 free_irq(mpc8xxx_spi->irq, mpc8xxx_spi); 181 182 if (mpc8xxx_spi->spi_remove) 183 mpc8xxx_spi->spi_remove(mpc8xxx_spi); 184 185 return 0; 186 } 187 188 int of_mpc8xxx_spi_probe(struct platform_device *ofdev) 189 { 190 struct device *dev = &ofdev->dev; 191 struct device_node *np = ofdev->dev.of_node; 192 struct mpc8xxx_spi_probe_info *pinfo; 193 struct fsl_spi_platform_data *pdata; 194 const void *prop; 195 int ret = -ENOMEM; 196 197 pinfo = devm_kzalloc(&ofdev->dev, sizeof(*pinfo), GFP_KERNEL); 198 if (!pinfo) 199 return ret; 200 201 pdata = &pinfo->pdata; 202 dev->platform_data = pdata; 203 204 /* Allocate bus num dynamically. */ 205 pdata->bus_num = -1; 206 207 #ifdef CONFIG_FSL_SOC 208 /* SPI controller is either clocked from QE or SoC clock. */ 209 pdata->sysclk = get_brgfreq(); 210 if (pdata->sysclk == -1) { 211 pdata->sysclk = fsl_get_sys_freq(); 212 if (pdata->sysclk == -1) 213 return -ENODEV; 214 } 215 #else 216 ret = of_property_read_u32(np, "clock-frequency", &pdata->sysclk); 217 if (ret) 218 return ret; 219 #endif 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