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Diffstat (limited to 'drivers/spi/altera_spi.c')
-rw-r--r--drivers/spi/altera_spi.c247
1 files changed, 0 insertions, 247 deletions
diff --git a/drivers/spi/altera_spi.c b/drivers/spi/altera_spi.c
deleted file mode 100644
index 4506e2741d..0000000000
--- a/drivers/spi/altera_spi.c
+++ /dev/null
@@ -1,247 +0,0 @@
-/*
- * (C) Copyright 2011 - Franck JULLIEN <elec4fun@gmail.com>
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- *
- */
-
-#include <common.h>
-#include <init.h>
-#include <driver.h>
-#include <spi/spi.h>
-#include <io.h>
-#include <asm/spi.h>
-#include <asm/nios2-io.h>
-#include <clock.h>
-
-static void altera_spi_cs_inactive(struct spi_device *spi);
-
-static int altera_spi_setup(struct spi_device *spi)
-{
- struct spi_master *master = spi->master;
- struct device_d spi_dev = spi->dev;
- struct altera_spi *altera_spi = container_of(master, struct altera_spi, master);
-
- if (spi->bits_per_word != altera_spi->databits) {
- dev_err(master->dev, " master doesn't support %d bits per word requested by %s\n",
- spi->bits_per_word, spi_dev.name);
- return -EINVAL;
- }
-
- if ((spi->mode & (SPI_CPHA | SPI_CPOL)) != altera_spi->mode) {
- dev_err(master->dev, " master doesn't support SPI_MODE%d requested by %s\n",
- spi->mode & (SPI_CPHA | SPI_CPOL), spi_dev.name);
- return -EINVAL;
- }
-
- if (spi->max_speed_hz < altera_spi->speed) {
- dev_err(master->dev, " frequency is too high for %s\n", spi_dev.name);
- return -EINVAL;
- }
-
- altera_spi_cs_inactive(spi);
-
- dev_dbg(master->dev, " mode 0x%08x, bits_per_word: %d, speed: %d\n",
- spi->mode, spi->bits_per_word, altera_spi->speed);
-
- return 0;
-}
-
-
-static unsigned int altera_spi_xchg_single(struct altera_spi *altera_spi, unsigned int data)
-{
- struct nios_spi *nios_spi = altera_spi->regs;
-
- while (!(readl(&nios_spi->status) & NIOS_SPI_TRDY));
- writel(data, &nios_spi->txdata);
-
- while (!(readl(&nios_spi->status) & NIOS_SPI_RRDY));
-
- return readl(&nios_spi->rxdata);
-}
-
-/*
- * When using SPI_CS_HIGH devices, only one device is allowed to be
- * connected to the Altera SPI master. This limitation is due to the
- * emulation of an active high CS by writing 0 to the slaveselect register
- * (this produce a '1' to all CS pins).
- */
-
-static void altera_spi_cs_active(struct spi_device *spi)
-{
- struct altera_spi *altera_spi = container_of(spi->master, struct altera_spi, master);
- struct nios_spi *nios_spi = altera_spi->regs;
- uint32_t tmp;
-
- if (spi->mode & SPI_CS_HIGH) {
- tmp = readw(&nios_spi->control);
- writew(tmp & ~NIOS_SPI_SSO, &nios_spi->control);
- writel(0, &nios_spi->slaveselect);
- } else {
- writel(1 << spi->chip_select, &nios_spi->slaveselect);
- tmp = readl(&nios_spi->control);
- writel(tmp | NIOS_SPI_SSO, &nios_spi->control);
- }
-}
-
-static void altera_spi_cs_inactive(struct spi_device *spi)
-{
- struct altera_spi *altera_spi = container_of(spi->master, struct altera_spi, master);
- struct nios_spi *nios_spi = altera_spi->regs;
- uint32_t tmp;
-
- if (spi->mode & SPI_CS_HIGH) {
- writel(1 << spi->chip_select, &nios_spi->slaveselect);
- tmp = readl(&nios_spi->control);
- writel(tmp | NIOS_SPI_SSO, &nios_spi->control);
- } else {
- tmp = readw(&nios_spi->control);
- writew(tmp & ~NIOS_SPI_SSO, &nios_spi->control);
- }
-}
-
-static unsigned altera_spi_do_xfer(struct spi_device *spi, struct spi_transfer *t)
-{
- struct altera_spi *altera_spi = container_of(spi->master, struct altera_spi, master);
- int word_len;
- unsigned retval = 0;
- u32 txval;
- u32 rxval;
-
- word_len = spi->bits_per_word;
-
- if (word_len <= 8) {
- const u8 *txbuf = t->tx_buf;
- u8 *rxbuf = t->rx_buf;
- int i = 0;
-
- while (i < t->len) {
- txval = txbuf ? txbuf[i] : 0;
- rxval = altera_spi_xchg_single(altera_spi, txval);
- if (rxbuf)
- rxbuf[i] = rxval;
- i++;
- retval++;
- }
- } else if (word_len <= 16) {
- const u16 *txbuf = t->tx_buf;
- u16 *rxbuf = t->rx_buf;
- int i = 0;
-
- while (i < t->len >> 1) {
- txval = txbuf ? txbuf[i] : 0;
- rxval = altera_spi_xchg_single(altera_spi, txval);
- if (rxbuf)
- rxbuf[i] = rxval;
- i++;
- retval += 2;
- }
- } else if (word_len <= 32) {
- const u32 *txbuf = t->tx_buf;
- u32 *rxbuf = t->rx_buf;
- int i = 0;
-
- while (i < t->len >> 2) {
- txval = txbuf ? txbuf[i] : 0;
- rxval = altera_spi_xchg_single(altera_spi, txval);
- if (rxbuf)
- rxbuf[i] = rxval;
- i++;
- retval += 4;
- }
- }
-
- return retval;
-}
-
-static int altera_spi_transfer(struct spi_device *spi, struct spi_message *mesg)
-{
- struct altera_spi *altera_spi = container_of(spi->master, struct altera_spi, master);
- struct nios_spi *nios_spi = altera_spi->regs;
- struct spi_transfer *t;
- unsigned int cs_change;
- const int nsecs = 50;
-
- altera_spi_cs_active(spi);
-
- cs_change = 0;
-
- mesg->actual_length = 0;
-
- list_for_each_entry(t, &mesg->transfers, transfer_list) {
-
- if (cs_change) {
- ndelay(nsecs);
- altera_spi_cs_inactive(spi);
- ndelay(nsecs);
- altera_spi_cs_active(spi);
- }
-
- cs_change = t->cs_change;
-
- mesg->actual_length += altera_spi_do_xfer(spi, t);
-
- if (cs_change) {
- altera_spi_cs_active(spi);
- }
- }
-
- /* Wait the end of any pending transfer */
- while ((readl(&nios_spi->status) & NIOS_SPI_TMT) == 0);
-
- if (!cs_change)
- altera_spi_cs_inactive(spi);
-
- return 0;
-}
-
-static int altera_spi_probe(struct device_d *dev)
-{
- struct resource *iores;
- struct spi_master *master;
- struct altera_spi *altera_spi;
- struct spi_altera_master *pdata = dev->platform_data;
- struct nios_spi *nios_spi;
-
- altera_spi = xzalloc(sizeof(*altera_spi));
-
- master = &altera_spi->master;
- master->dev = dev;
-
- master->setup = altera_spi_setup;
- master->transfer = altera_spi_transfer;
- master->num_chipselect = pdata->num_chipselect;
- master->bus_num = pdata->bus_num;
-
- iores = dev_request_mem_resource(dev, 0);
- if (IS_ERR(iores))
- return PTR_ERR(iores);
- altera_spi->regs = IOMEM(iores->start);
-
- altera_spi->databits = pdata->databits;
- altera_spi->speed = pdata->speed;
- altera_spi->mode = pdata->spi_mode;
-
- nios_spi = altera_spi->regs;
- writel(0, &nios_spi->slaveselect);
- writel(0, &nios_spi->control);
-
- spi_register_master(master);
-
- return 0;
-}
-
-static struct driver_d altera_spi_driver = {
- .name = "altera_spi",
- .probe = altera_spi_probe,
-};
-device_platform_driver(altera_spi_driver);
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-25 01:18:00 +0000