spi/mpc5121: Add SPI master driver for MPC5121 PSC
Anatolij Gustschin [Fri, 30 Apr 2010 13:21:27 +0000 (13:21 +0000)]
Signed-off-by: John Rigby <jcrigby@gmail.com>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

arch/powerpc/include/asm/mpc52xx_psc.h
drivers/spi/Kconfig
drivers/spi/Makefile
drivers/spi/mpc512x_psc_spi.c [new file with mode: 0644]

index 42561f4..ecc4fc6 100644 (file)
@@ -248,6 +248,7 @@ struct mpc52xx_psc_fifo {
        u16             tflwfptr;       /* PSC + 0x9e */
 };
 
+#define MPC512x_PSC_FIFO_EOF           0x100
 #define MPC512x_PSC_FIFO_RESET_SLICE   0x80
 #define MPC512x_PSC_FIFO_ENABLE_SLICE  0x01
 #define MPC512x_PSC_FIFO_ENABLE_DMA    0x04
index 2b2f4c3..aacc0ed 100644 (file)
@@ -175,6 +175,13 @@ config SPI_MPC52xx_PSC
          This enables using the Freescale MPC52xx Programmable Serial
          Controller in master SPI mode.
 
+config SPI_MPC512x_PSC
+       tristate "Freescale MPC512x PSC SPI controller"
+       depends on SPI_MASTER && PPC_MPC512x
+       help
+         This enables using the Freescale MPC5121 Programmable Serial
+         Controller in SPI master mode.
+
 config SPI_MPC8xxx
        tristate "Freescale MPC8xxx SPI controller"
        depends on FSL_SOC
index 377f845..e9cbd18 100644 (file)
@@ -31,6 +31,7 @@ obj-$(CONFIG_SPI_OMAP24XX)            += omap2_mcspi.o
 obj-$(CONFIG_SPI_OMAP_100K)            += omap_spi_100k.o
 obj-$(CONFIG_SPI_ORION)                        += orion_spi.o
 obj-$(CONFIG_SPI_PL022)                        += amba-pl022.o
+obj-$(CONFIG_SPI_MPC512x_PSC)          += mpc512x_psc_spi.o
 obj-$(CONFIG_SPI_MPC52xx_PSC)          += mpc52xx_psc_spi.o
 obj-$(CONFIG_SPI_MPC52xx)              += mpc52xx_spi.o
 obj-$(CONFIG_SPI_MPC8xxx)              += spi_mpc8xxx.o
diff --git a/drivers/spi/mpc512x_psc_spi.c b/drivers/spi/mpc512x_psc_spi.c
new file mode 100644 (file)
index 0000000..28a126d
--- /dev/null
@@ -0,0 +1,576 @@
+/*
+ * 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");