v4.19.13 snapshot.
diff --git a/drivers/spi/spi-altera.c b/drivers/spi/spi-altera.c
new file mode 100644
index 0000000..a5adf0d
--- /dev/null
+++ b/drivers/spi/spi-altera.c
@@ -0,0 +1,249 @@
+/*
+ * Altera SPI driver
+ *
+ * Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * Based on spi_s3c24xx.c, which is:
+ * Copyright (c) 2006 Ben Dooks
+ * Copyright (c) 2006 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+#define DRV_NAME "spi_altera"
+
+#define ALTERA_SPI_RXDATA 0
+#define ALTERA_SPI_TXDATA 4
+#define ALTERA_SPI_STATUS 8
+#define ALTERA_SPI_CONTROL 12
+#define ALTERA_SPI_SLAVE_SEL 20
+
+#define ALTERA_SPI_STATUS_ROE_MSK 0x8
+#define ALTERA_SPI_STATUS_TOE_MSK 0x10
+#define ALTERA_SPI_STATUS_TMT_MSK 0x20
+#define ALTERA_SPI_STATUS_TRDY_MSK 0x40
+#define ALTERA_SPI_STATUS_RRDY_MSK 0x80
+#define ALTERA_SPI_STATUS_E_MSK 0x100
+
+#define ALTERA_SPI_CONTROL_IROE_MSK 0x8
+#define ALTERA_SPI_CONTROL_ITOE_MSK 0x10
+#define ALTERA_SPI_CONTROL_ITRDY_MSK 0x40
+#define ALTERA_SPI_CONTROL_IRRDY_MSK 0x80
+#define ALTERA_SPI_CONTROL_IE_MSK 0x100
+#define ALTERA_SPI_CONTROL_SSO_MSK 0x400
+
+struct altera_spi {
+ void __iomem *base;
+ int irq;
+ int len;
+ int count;
+ int bytes_per_word;
+ unsigned long imr;
+
+ /* data buffers */
+ const unsigned char *tx;
+ unsigned char *rx;
+};
+
+static inline struct altera_spi *altera_spi_to_hw(struct spi_device *sdev)
+{
+ return spi_master_get_devdata(sdev->master);
+}
+
+static void altera_spi_set_cs(struct spi_device *spi, bool is_high)
+{
+ struct altera_spi *hw = altera_spi_to_hw(spi);
+
+ if (is_high) {
+ hw->imr &= ~ALTERA_SPI_CONTROL_SSO_MSK;
+ writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
+ writel(0, hw->base + ALTERA_SPI_SLAVE_SEL);
+ } else {
+ writel(BIT(spi->chip_select), hw->base + ALTERA_SPI_SLAVE_SEL);
+ hw->imr |= ALTERA_SPI_CONTROL_SSO_MSK;
+ writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
+ }
+}
+
+static void altera_spi_tx_word(struct altera_spi *hw)
+{
+ unsigned int txd = 0;
+
+ if (hw->tx) {
+ switch (hw->bytes_per_word) {
+ case 1:
+ txd = hw->tx[hw->count];
+ break;
+ case 2:
+ txd = (hw->tx[hw->count * 2]
+ | (hw->tx[hw->count * 2 + 1] << 8));
+ break;
+ }
+ }
+
+ writel(txd, hw->base + ALTERA_SPI_TXDATA);
+}
+
+static void altera_spi_rx_word(struct altera_spi *hw)
+{
+ unsigned int rxd;
+
+ rxd = readl(hw->base + ALTERA_SPI_RXDATA);
+ if (hw->rx) {
+ switch (hw->bytes_per_word) {
+ case 1:
+ hw->rx[hw->count] = rxd;
+ break;
+ case 2:
+ hw->rx[hw->count * 2] = rxd;
+ hw->rx[hw->count * 2 + 1] = rxd >> 8;
+ break;
+ }
+ }
+
+ hw->count++;
+}
+
+static int altera_spi_txrx(struct spi_master *master,
+ struct spi_device *spi, struct spi_transfer *t)
+{
+ struct altera_spi *hw = spi_master_get_devdata(master);
+
+ hw->tx = t->tx_buf;
+ hw->rx = t->rx_buf;
+ hw->count = 0;
+ hw->bytes_per_word = DIV_ROUND_UP(t->bits_per_word, 8);
+ hw->len = t->len / hw->bytes_per_word;
+
+ if (hw->irq >= 0) {
+ /* enable receive interrupt */
+ hw->imr |= ALTERA_SPI_CONTROL_IRRDY_MSK;
+ writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
+
+ /* send the first byte */
+ altera_spi_tx_word(hw);
+ } else {
+ while (hw->count < hw->len) {
+ altera_spi_tx_word(hw);
+
+ while (!(readl(hw->base + ALTERA_SPI_STATUS) &
+ ALTERA_SPI_STATUS_RRDY_MSK))
+ cpu_relax();
+
+ altera_spi_rx_word(hw);
+ }
+ spi_finalize_current_transfer(master);
+ }
+
+ return t->len;
+}
+
+static irqreturn_t altera_spi_irq(int irq, void *dev)
+{
+ struct spi_master *master = dev;
+ struct altera_spi *hw = spi_master_get_devdata(master);
+
+ altera_spi_rx_word(hw);
+
+ if (hw->count < hw->len) {
+ altera_spi_tx_word(hw);
+ } else {
+ /* disable receive interrupt */
+ hw->imr &= ~ALTERA_SPI_CONTROL_IRRDY_MSK;
+ writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
+
+ spi_finalize_current_transfer(master);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int altera_spi_probe(struct platform_device *pdev)
+{
+ struct altera_spi *hw;
+ struct spi_master *master;
+ struct resource *res;
+ int err = -ENODEV;
+
+ master = spi_alloc_master(&pdev->dev, sizeof(struct altera_spi));
+ if (!master)
+ return err;
+
+ /* setup the master state. */
+ master->bus_num = pdev->id;
+ master->num_chipselect = 16;
+ master->mode_bits = SPI_CS_HIGH;
+ master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16);
+ master->dev.of_node = pdev->dev.of_node;
+ master->transfer_one = altera_spi_txrx;
+ master->set_cs = altera_spi_set_cs;
+
+ hw = spi_master_get_devdata(master);
+
+ /* find and map our resources */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ hw->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(hw->base)) {
+ err = PTR_ERR(hw->base);
+ goto exit;
+ }
+ /* program defaults into the registers */
+ hw->imr = 0; /* disable spi interrupts */
+ writel(hw->imr, hw->base + ALTERA_SPI_CONTROL);
+ writel(0, hw->base + ALTERA_SPI_STATUS); /* clear status reg */
+ if (readl(hw->base + ALTERA_SPI_STATUS) & ALTERA_SPI_STATUS_RRDY_MSK)
+ readl(hw->base + ALTERA_SPI_RXDATA); /* flush rxdata */
+ /* irq is optional */
+ hw->irq = platform_get_irq(pdev, 0);
+ if (hw->irq >= 0) {
+ err = devm_request_irq(&pdev->dev, hw->irq, altera_spi_irq, 0,
+ pdev->name, master);
+ if (err)
+ goto exit;
+ }
+
+ err = devm_spi_register_master(&pdev->dev, master);
+ if (err)
+ goto exit;
+ dev_info(&pdev->dev, "base %p, irq %d\n", hw->base, hw->irq);
+
+ return 0;
+exit:
+ spi_master_put(master);
+ return err;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id altera_spi_match[] = {
+ { .compatible = "ALTR,spi-1.0", },
+ { .compatible = "altr,spi-1.0", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, altera_spi_match);
+#endif /* CONFIG_OF */
+
+static struct platform_driver altera_spi_driver = {
+ .probe = altera_spi_probe,
+ .driver = {
+ .name = DRV_NAME,
+ .pm = NULL,
+ .of_match_table = of_match_ptr(altera_spi_match),
+ },
+};
+module_platform_driver(altera_spi_driver);
+
+MODULE_DESCRIPTION("Altera SPI driver");
+MODULE_AUTHOR("Thomas Chou <thomas@wytron.com.tw>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRV_NAME);