--- /dev/null
+/*
+ * MPC512x PSC in SPI mode driver.
+ *
+ * Copyright (C) 2007,2008 Freescale Semiconductor Inc.
+ * Original port from 52xx driver:
+ * Hongjun Chen <hong-jun.chen@freescale.com>
+ *
+ * Fork of mpc52xx_psc_spi.c:
+ * Copyright (C) 2006 TOPTICA Photonics AG., Dragos Carp
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/of_platform.h>
+#include <linux/workqueue.h>
+#include <linux/completion.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/spi/spi.h>
+#include <linux/fsl_devices.h>
+#include <asm/mpc52xx_psc.h>
+
+struct mpc512x_psc_spi {
+ void (*cs_control)(struct spi_device *spi, bool on);
+ u32 sysclk;
+
+ /* driver internal data */
+ struct mpc52xx_psc __iomem *psc;
+ struct mpc512x_psc_fifo __iomem *fifo;
+ unsigned int irq;
+ u8 bits_per_word;
+ u8 busy;
+ u32 mclk;
+ u8 eofbyte;
+
+ struct workqueue_struct *workqueue;
+ struct work_struct work;
+
+ struct list_head queue;
+ spinlock_t lock; /* Message queue lock */
+
+ struct completion done;
+};
+
+/* controller state */
+struct mpc512x_psc_spi_cs {
+ int bits_per_word;
+ int speed_hz;
+};
+
+/* set clock freq, clock ramp, bits per work
+ * if t is NULL then reset the values to the default values
+ */
+static int mpc512x_psc_spi_transfer_setup(struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct mpc512x_psc_spi_cs *cs = spi->controller_state;
+
+ cs->speed_hz = (t && t->speed_hz)
+ ? t->speed_hz : spi->max_speed_hz;
+ cs->bits_per_word = (t && t->bits_per_word)
+ ? t->bits_per_word : spi->bits_per_word;
+ cs->bits_per_word = ((cs->bits_per_word + 7) / 8) * 8;
+ return 0;
+}
+
+static void mpc512x_psc_spi_activate_cs(struct spi_device *spi)
+{
+ struct mpc512x_psc_spi_cs *cs = spi->controller_state;
+ struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master);
+ struct mpc52xx_psc __iomem *psc = mps->psc;
+ u32 sicr;
+ u32 ccr;
+ u16 bclkdiv;
+
+ sicr = in_be32(&psc->sicr);
+
+ /* Set clock phase and polarity */
+ if (spi->mode & SPI_CPHA)
+ sicr |= 0x00001000;
+ else
+ sicr &= ~0x00001000;
+
+ if (spi->mode & SPI_CPOL)
+ sicr |= 0x00002000;
+ else
+ sicr &= ~0x00002000;
+
+ if (spi->mode & SPI_LSB_FIRST)
+ sicr |= 0x10000000;
+ else
+ sicr &= ~0x10000000;
+ out_be32(&psc->sicr, sicr);
+
+ ccr = in_be32(&psc->ccr);
+ ccr &= 0xFF000000;
+ if (cs->speed_hz)
+ bclkdiv = (mps->mclk / cs->speed_hz) - 1;
+ else
+ bclkdiv = (mps->mclk / 1000000) - 1; /* default 1MHz */
+
+ ccr |= (((bclkdiv & 0xff) << 16) | (((bclkdiv >> 8) & 0xff) << 8));
+ out_be32(&psc->ccr, ccr);
+ mps->bits_per_word = cs->bits_per_word;
+
+ if (mps->cs_control)
+ mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0);
+}
+
+static void mpc512x_psc_spi_deactivate_cs(struct spi_device *spi)
+{
+ struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master);
+
+ if (mps->cs_control)
+ mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
+
+}
+
+/* extract and scale size field in txsz or rxsz */
+#define MPC512x_PSC_FIFO_SZ(sz) ((sz & 0x7ff) << 2);
+
+#define EOFBYTE 1
+
+static int mpc512x_psc_spi_transfer_rxtx(struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master);
+ struct mpc52xx_psc __iomem *psc = mps->psc;
+ struct mpc512x_psc_fifo __iomem *fifo = mps->fifo;
+ size_t len = t->len;
+ u8 *tx_buf = (u8 *)t->tx_buf;
+ u8 *rx_buf = (u8 *)t->rx_buf;
+
+ if (!tx_buf && !rx_buf && t->len)
+ return -EINVAL;
+
+ /* Zero MR2 */
+ in_8(&psc->mode);
+ out_8(&psc->mode, 0x0);
+
+ while (len) {
+ int count;
+ int i;
+ u8 data;
+ size_t fifosz;
+ int rxcount;
+
+ /*
+ * The number of bytes that can be sent at a time
+ * depends on the fifo size.
+ */
+ fifosz = MPC512x_PSC_FIFO_SZ(in_be32(&fifo->txsz));
+ count = min(fifosz, len);
+
+ for (i = count; i > 0; i--) {
+ data = tx_buf ? *tx_buf++ : 0;
+ if (len == EOFBYTE)
+ setbits32(&fifo->txcmd, MPC512x_PSC_FIFO_EOF);
+ out_8(&fifo->txdata_8, data);
+ len--;
+ }
+
+ INIT_COMPLETION(mps->done);
+
+ /* interrupt on tx fifo empty */
+ out_be32(&fifo->txisr, MPC512x_PSC_FIFO_EMPTY);
+ out_be32(&fifo->tximr, MPC512x_PSC_FIFO_EMPTY);
+
+ /* enable transmiter/receiver */
+ out_8(&psc->command,
+ MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
+
+ wait_for_completion(&mps->done);
+
+ mdelay(1);
+
+ /* rx fifo should have count bytes in it */
+ rxcount = in_be32(&fifo->rxcnt);
+ if (rxcount != count)
+ mdelay(1);
+
+ rxcount = in_be32(&fifo->rxcnt);
+ if (rxcount != count) {
+ dev_warn(&spi->dev, "expected %d bytes in rx fifo "
+ "but got %d\n", count, rxcount);
+ }
+
+ rxcount = min(rxcount, count);
+ for (i = rxcount; i > 0; i--) {
+ data = in_8(&fifo->rxdata_8);
+ if (rx_buf)
+ *rx_buf++ = data;
+ }
+ while (in_be32(&fifo->rxcnt)) {
+ in_8(&fifo->rxdata_8);
+ }
+
+ out_8(&psc->command,
+ MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
+ }
+ /* disable transmiter/receiver and fifo interrupt */
+ out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
+ out_be32(&fifo->tximr, 0);
+ return 0;
+}
+
+static void mpc512x_psc_spi_work(struct work_struct *work)
+{
+ struct mpc512x_psc_spi *mps = container_of(work,
+ struct mpc512x_psc_spi,
+ work);
+
+ spin_lock_irq(&mps->lock);
+ mps->busy = 1;
+ while (!list_empty(&mps->queue)) {
+ struct spi_message *m;
+ struct spi_device *spi;
+ struct spi_transfer *t = NULL;
+ unsigned cs_change;
+ int status;
+
+ m = container_of(mps->queue.next, struct spi_message, queue);
+ list_del_init(&m->queue);
+ spin_unlock_irq(&mps->lock);
+
+ spi = m->spi;
+ cs_change = 1;
+ status = 0;
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ if (t->bits_per_word || t->speed_hz) {
+ status = mpc512x_psc_spi_transfer_setup(spi, t);
+ if (status < 0)
+ break;
+ }
+
+ if (cs_change)
+ mpc512x_psc_spi_activate_cs(spi);
+ cs_change = t->cs_change;
+
+ status = mpc512x_psc_spi_transfer_rxtx(spi, t);
+ if (status)
+ break;
+ m->actual_length += t->len;
+
+ if (t->delay_usecs)
+ udelay(t->delay_usecs);
+
+ if (cs_change)
+ mpc512x_psc_spi_deactivate_cs(spi);
+ }
+
+ m->status = status;
+ m->complete(m->context);
+
+ if (status || !cs_change)
+ mpc512x_psc_spi_deactivate_cs(spi);
+
+ mpc512x_psc_spi_transfer_setup(spi, NULL);
+
+ spin_lock_irq(&mps->lock);
+ }
+ mps->busy = 0;
+ spin_unlock_irq(&mps->lock);
+}
+
+static int mpc512x_psc_spi_setup(struct spi_device *spi)
+{
+ struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master);
+ struct mpc512x_psc_spi_cs *cs = spi->controller_state;
+ unsigned long flags;
+
+ if (spi->bits_per_word % 8)
+ return -EINVAL;
+
+ if (!cs) {
+ cs = kzalloc(sizeof *cs, GFP_KERNEL);
+ if (!cs)
+ return -ENOMEM;
+ spi->controller_state = cs;
+ }
+
+ cs->bits_per_word = spi->bits_per_word;
+ cs->speed_hz = spi->max_speed_hz;
+
+ spin_lock_irqsave(&mps->lock, flags);
+ if (!mps->busy)
+ mpc512x_psc_spi_deactivate_cs(spi);
+ spin_unlock_irqrestore(&mps->lock, flags);
+
+ return 0;
+}
+
+static int mpc512x_psc_spi_transfer(struct spi_device *spi,
+ struct spi_message *m)
+{
+ struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master);
+ unsigned long flags;
+
+ m->actual_length = 0;
+ m->status = -EINPROGRESS;
+
+ spin_lock_irqsave(&mps->lock, flags);
+ list_add_tail(&m->queue, &mps->queue);
+ queue_work(mps->workqueue, &mps->work);
+ spin_unlock_irqrestore(&mps->lock, flags);
+
+ return 0;
+}
+
+static void mpc512x_psc_spi_cleanup(struct spi_device *spi)
+{
+ kfree(spi->controller_state);
+}
+
+static int mpc512x_psc_spi_port_config(struct spi_master *master,
+ struct mpc512x_psc_spi *mps)
+{
+ struct mpc52xx_psc __iomem *psc = mps->psc;
+ struct mpc512x_psc_fifo __iomem *fifo = mps->fifo;
+ struct clk *spiclk;
+ int ret = 0;
+ char name[32];
+ u32 sicr;
+ u32 ccr;
+ u16 bclkdiv;
+
+ sprintf(name, "psc%d_mclk", master->bus_num);
+ spiclk = clk_get(&master->dev, name);
+ clk_enable(spiclk);
+ mps->mclk = clk_get_rate(spiclk);
+ clk_put(spiclk);
+
+ /* Reset the PSC into a known state */
+ out_8(&psc->command, MPC52xx_PSC_RST_RX);
+ out_8(&psc->command, MPC52xx_PSC_RST_TX);
+ out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
+
+ /* Disable psc interrupts all useful interrupts are in fifo */
+ out_be16(&psc->isr_imr.imr, 0);
+
+ /* Disable fifo interrupts, will be enabled later */
+ out_be32(&fifo->tximr, 0);
+ out_be32(&fifo->rximr, 0);
+
+ /* Setup fifo slice address and size */
+ /*out_be32(&fifo->txsz, 0x0fe00004);*/
+ /*out_be32(&fifo->rxsz, 0x0ff00004);*/
+
+ sicr = 0x01000000 | /* SIM = 0001 -- 8 bit */
+ 0x00800000 | /* GenClk = 1 -- internal clk */
+ 0x00008000 | /* SPI = 1 */
+ 0x00004000 | /* MSTR = 1 -- SPI master */
+ 0x00000800; /* UseEOF = 1 -- SS low until EOF */
+
+ out_be32(&psc->sicr, sicr);
+
+ ccr = in_be32(&psc->ccr);
+ ccr &= 0xFF000000;
+ bclkdiv = (mps->mclk / 1000000) - 1; /* default 1MHz */
+ ccr |= (((bclkdiv & 0xff) << 16) | (((bclkdiv >> 8) & 0xff) << 8));
+ out_be32(&psc->ccr, ccr);
+
+ /* Set 2ms DTL delay */
+ out_8(&psc->ctur, 0x00);
+ out_8(&psc->ctlr, 0x82);
+
+ /* we don't use the alarms */
+ out_be32(&fifo->rxalarm, 0xfff);
+ out_be32(&fifo->txalarm, 0);
+
+ /* Enable FIFO slices for Rx/Tx */
+ out_be32(&fifo->rxcmd,
+ MPC512x_PSC_FIFO_ENABLE_SLICE | MPC512x_PSC_FIFO_ENABLE_DMA);
+ out_be32(&fifo->txcmd,
+ MPC512x_PSC_FIFO_ENABLE_SLICE | MPC512x_PSC_FIFO_ENABLE_DMA);
+
+ mps->bits_per_word = 8;
+
+ return ret;
+}
+
+static irqreturn_t mpc512x_psc_spi_isr(int irq, void *dev_id)
+{
+ struct mpc512x_psc_spi *mps = (struct mpc512x_psc_spi *)dev_id;
+ struct mpc512x_psc_fifo __iomem *fifo = mps->fifo;
+
+ /* clear interrupt and wake up the work queue */
+ if (in_be32(&fifo->txisr) &
+ in_be32(&fifo->tximr) & MPC512x_PSC_FIFO_EMPTY) {
+ out_be32(&fifo->txisr, MPC512x_PSC_FIFO_EMPTY);
+ out_be32(&fifo->tximr, 0);
+ complete(&mps->done);
+ return IRQ_HANDLED;
+ }
+ return IRQ_NONE;
+}
+
+/* bus_num is used only for the case dev->platform_data == NULL */
+static int __init mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr,
+ u32 size, unsigned int irq,
+ s16 bus_num)
+{
+ struct fsl_spi_platform_data *pdata = dev->platform_data;
+ struct mpc512x_psc_spi *mps;
+ struct spi_master *master;
+ int ret;
+ void *tempp;
+
+ master = spi_alloc_master(dev, sizeof *mps);
+ if (master == NULL)
+ return -ENOMEM;
+
+ dev_set_drvdata(dev, master);
+ mps = spi_master_get_devdata(master);
+ mps->irq = irq;
+
+ if (pdata == NULL) {
+ dev_err(dev, "probe called without platform data, no "
+ "cs_control function will be called\n");
+ mps->cs_control = NULL;
+ mps->sysclk = 0;
+ master->bus_num = bus_num;
+ master->num_chipselect = 255;
+ } else {
+ mps->cs_control = pdata->cs_control;
+ mps->sysclk = pdata->sysclk;
+ master->bus_num = pdata->bus_num;
+ master->num_chipselect = pdata->max_chipselect;
+ }
+
+ master->setup = mpc512x_psc_spi_setup;
+ master->transfer = mpc512x_psc_spi_transfer;
+ master->cleanup = mpc512x_psc_spi_cleanup;
+
+ tempp = ioremap(regaddr, size);
+ if (!tempp) {
+ dev_err(dev, "could not ioremap I/O port range\n");
+ ret = -EFAULT;
+ goto free_master;
+ }
+ mps->psc = tempp;
+ mps->fifo =
+ (struct mpc512x_psc_fifo *)(tempp + sizeof(struct mpc52xx_psc));
+
+ ret = request_irq(mps->irq, mpc512x_psc_spi_isr, IRQF_SHARED,
+ "mpc512x-psc-spi", mps);
+ if (ret)
+ goto free_master;
+
+ ret = mpc512x_psc_spi_port_config(master, mps);
+ if (ret < 0)
+ goto free_irq;
+
+ spin_lock_init(&mps->lock);
+ init_completion(&mps->done);
+ INIT_WORK(&mps->work, mpc512x_psc_spi_work);
+ INIT_LIST_HEAD(&mps->queue);
+
+ mps->workqueue =
+ create_singlethread_workqueue(dev_name(master->dev.parent));
+ if (mps->workqueue == NULL) {
+ ret = -EBUSY;
+ goto free_irq;
+ }
+
+ ret = spi_register_master(master);
+ if (ret < 0)
+ goto unreg_master;
+
+ return ret;
+
+unreg_master:
+ destroy_workqueue(mps->workqueue);
+free_irq:
+ free_irq(mps->irq, mps);
+free_master:
+ if (mps->psc)
+ iounmap(mps->psc);
+ spi_master_put(master);
+
+ return ret;
+}
+
+static int __exit mpc512x_psc_spi_do_remove(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct mpc512x_psc_spi *mps = spi_master_get_devdata(master);
+
+ flush_workqueue(mps->workqueue);
+ destroy_workqueue(mps->workqueue);
+ spi_unregister_master(master);
+ free_irq(mps->irq, mps);
+ if (mps->psc)
+ iounmap(mps->psc);
+
+ return 0;
+}
+
+static int __init mpc512x_psc_spi_of_probe(struct of_device *op,
+ const struct of_device_id *match)
+{
+ const u32 *regaddr_p;
+ u64 regaddr64, size64;
+ s16 id = -1;
+
+ regaddr_p = of_get_address(op->node, 0, &size64, NULL);
+ if (!regaddr_p) {
+ dev_err(&op->dev, "Invalid PSC address\n");
+ return -EINVAL;
+ }
+ regaddr64 = of_translate_address(op->node, regaddr_p);
+
+ /* get PSC id (0..11, used by port_config) */
+ if (op->dev.platform_data == NULL) {
+ const u32 *psc_nump;
+
+ psc_nump = of_get_property(op->node, "cell-index", NULL);
+ if (!psc_nump || *psc_nump > 11) {
+ dev_err(&op->dev, "mpc512x_psc_spi: Device node %s "
+ "has invalid cell-index property\n",
+ op->node->full_name);
+ return -EINVAL;
+ }
+ id = *psc_nump;
+ }
+
+ return mpc512x_psc_spi_do_probe(&op->dev, (u32) regaddr64, (u32) size64,
+ irq_of_parse_and_map(op->node, 0), id);
+}
+
+static int __exit mpc512x_psc_spi_of_remove(struct of_device *op)
+{
+ return mpc512x_psc_spi_do_remove(&op->dev);
+}
+
+static struct of_device_id mpc512x_psc_spi_of_match[] = {
+ { .compatible = "fsl,mpc5121-psc-spi", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, mpc512x_psc_spi_of_match);
+
+static struct of_platform_driver mpc512x_psc_spi_of_driver = {
+ .match_table = mpc512x_psc_spi_of_match,
+ .probe = mpc512x_psc_spi_of_probe,
+ .remove = __exit_p(mpc512x_psc_spi_of_remove),
+ .driver = {
+ .name = "mpc512x-psc-spi",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init mpc512x_psc_spi_init(void)
+{
+ return of_register_platform_driver(&mpc512x_psc_spi_of_driver);
+}
+module_init(mpc512x_psc_spi_init);
+
+static void __exit mpc512x_psc_spi_exit(void)
+{
+ of_unregister_platform_driver(&mpc512x_psc_spi_of_driver);
+}
+module_exit(mpc512x_psc_spi_exit);
+
+MODULE_AUTHOR("John Rigby");
+MODULE_DESCRIPTION("MPC512x PSC SPI Driver");
+MODULE_LICENSE("GPL");
projects / cascardo / linux.git / commitdiff