+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (c) 2009 Nuvoton technology.
- * Wan ZongShun <mcuos.com@gmail.com>
- */
-
-#include <linux/module.h>
-#include <linux/spinlock.h>
-#include <linux/interrupt.h>
-#include <linux/delay.h>
-#include <linux/errno.h>
-#include <linux/err.h>
-#include <linux/clk.h>
-#include <linux/device.h>
-#include <linux/platform_device.h>
-#include <linux/gpio.h>
-#include <linux/io.h>
-#include <linux/slab.h>
-
-#include <linux/spi/spi.h>
-#include <linux/spi/spi_bitbang.h>
-
-#include <linux/platform_data/spi-nuc900.h>
-
-/* usi registers offset */
-#define USI_CNT 0x00
-#define USI_DIV 0x04
-#define USI_SSR 0x08
-#define USI_RX0 0x10
-#define USI_TX0 0x10
-
-/* usi register bit */
-#define ENINT (0x01 << 17)
-#define ENFLG (0x01 << 16)
-#define SLEEP (0x0f << 12)
-#define TXNUM (0x03 << 8)
-#define TXBITLEN (0x1f << 3)
-#define TXNEG (0x01 << 2)
-#define RXNEG (0x01 << 1)
-#define LSB (0x01 << 10)
-#define SELECTLEV (0x01 << 2)
-#define SELECTPOL (0x01 << 31)
-#define SELECTSLAVE 0x01
-#define GOBUSY 0x01
-
-struct nuc900_spi {
- struct spi_bitbang bitbang;
- struct completion done;
- void __iomem *regs;
- int irq;
- int len;
- int count;
- const unsigned char *tx;
- unsigned char *rx;
- struct clk *clk;
- struct spi_master *master;
- struct nuc900_spi_info *pdata;
- spinlock_t lock;
-};
-
-static inline struct nuc900_spi *to_hw(struct spi_device *sdev)
-{
- return spi_master_get_devdata(sdev->master);
-}
-
-static void nuc900_slave_select(struct spi_device *spi, unsigned int ssr)
-{
- struct nuc900_spi *hw = to_hw(spi);
- unsigned int val;
- unsigned int cs = spi->mode & SPI_CS_HIGH ? 1 : 0;
- unsigned int cpol = spi->mode & SPI_CPOL ? 1 : 0;
- unsigned long flags;
-
- spin_lock_irqsave(&hw->lock, flags);
-
- val = __raw_readl(hw->regs + USI_SSR);
-
- if (!cs)
- val &= ~SELECTLEV;
- else
- val |= SELECTLEV;
-
- if (!ssr)
- val &= ~SELECTSLAVE;
- else
- val |= SELECTSLAVE;
-
- __raw_writel(val, hw->regs + USI_SSR);
-
- val = __raw_readl(hw->regs + USI_CNT);
-
- if (!cpol)
- val &= ~SELECTPOL;
- else
- val |= SELECTPOL;
-
- __raw_writel(val, hw->regs + USI_CNT);
-
- spin_unlock_irqrestore(&hw->lock, flags);
-}
-
-static void nuc900_spi_chipsel(struct spi_device *spi, int value)
-{
- switch (value) {
- case BITBANG_CS_INACTIVE:
- nuc900_slave_select(spi, 0);
- break;
-
- case BITBANG_CS_ACTIVE:
- nuc900_slave_select(spi, 1);
- break;
- }
-}
-
-static void nuc900_spi_setup_txnum(struct nuc900_spi *hw, unsigned int txnum)
-{
- unsigned int val;
- unsigned long flags;
-
- spin_lock_irqsave(&hw->lock, flags);
-
- val = __raw_readl(hw->regs + USI_CNT) & ~TXNUM;
-
- if (txnum)
- val |= txnum << 0x08;
-
- __raw_writel(val, hw->regs + USI_CNT);
-
- spin_unlock_irqrestore(&hw->lock, flags);
-
-}
-
-static void nuc900_spi_setup_txbitlen(struct nuc900_spi *hw,
- unsigned int txbitlen)
-{
- unsigned int val;
- unsigned long flags;
-
- spin_lock_irqsave(&hw->lock, flags);
-
- val = __raw_readl(hw->regs + USI_CNT) & ~TXBITLEN;
-
- val |= (txbitlen << 0x03);
-
- __raw_writel(val, hw->regs + USI_CNT);
-
- spin_unlock_irqrestore(&hw->lock, flags);
-}
-
-static void nuc900_spi_gobusy(struct nuc900_spi *hw)
-{
- unsigned int val;
- unsigned long flags;
-
- spin_lock_irqsave(&hw->lock, flags);
-
- val = __raw_readl(hw->regs + USI_CNT);
-
- val |= GOBUSY;
-
- __raw_writel(val, hw->regs + USI_CNT);
-
- spin_unlock_irqrestore(&hw->lock, flags);
-}
-
-static inline unsigned int hw_txbyte(struct nuc900_spi *hw, int count)
-{
- return hw->tx ? hw->tx[count] : 0;
-}
-
-static int nuc900_spi_txrx(struct spi_device *spi, struct spi_transfer *t)
-{
- struct nuc900_spi *hw = to_hw(spi);
-
- hw->tx = t->tx_buf;
- hw->rx = t->rx_buf;
- hw->len = t->len;
- hw->count = 0;
-
- __raw_writel(hw_txbyte(hw, 0x0), hw->regs + USI_TX0);
-
- nuc900_spi_gobusy(hw);
-
- wait_for_completion(&hw->done);
-
- return hw->count;
-}
-
-static irqreturn_t nuc900_spi_irq(int irq, void *dev)
-{
- struct nuc900_spi *hw = dev;
- unsigned int status;
- unsigned int count = hw->count;
-
- status = __raw_readl(hw->regs + USI_CNT);
- __raw_writel(status, hw->regs + USI_CNT);
-
- if (status & ENFLG) {
- hw->count++;
-
- if (hw->rx)
- hw->rx[count] = __raw_readl(hw->regs + USI_RX0);
- count++;
-
- if (count < hw->len) {
- __raw_writel(hw_txbyte(hw, count), hw->regs + USI_TX0);
- nuc900_spi_gobusy(hw);
- } else {
- complete(&hw->done);
- }
-
- return IRQ_HANDLED;
- }
-
- complete(&hw->done);
- return IRQ_HANDLED;
-}
-
-static void nuc900_tx_edge(struct nuc900_spi *hw, unsigned int edge)
-{
- unsigned int val;
- unsigned long flags;
-
- spin_lock_irqsave(&hw->lock, flags);
-
- val = __raw_readl(hw->regs + USI_CNT);
-
- if (edge)
- val |= TXNEG;
- else
- val &= ~TXNEG;
- __raw_writel(val, hw->regs + USI_CNT);
-
- spin_unlock_irqrestore(&hw->lock, flags);
-}
-
-static void nuc900_rx_edge(struct nuc900_spi *hw, unsigned int edge)
-{
- unsigned int val;
- unsigned long flags;
-
- spin_lock_irqsave(&hw->lock, flags);
-
- val = __raw_readl(hw->regs + USI_CNT);
-
- if (edge)
- val |= RXNEG;
- else
- val &= ~RXNEG;
- __raw_writel(val, hw->regs + USI_CNT);
-
- spin_unlock_irqrestore(&hw->lock, flags);
-}
-
-static void nuc900_send_first(struct nuc900_spi *hw, unsigned int lsb)
-{
- unsigned int val;
- unsigned long flags;
-
- spin_lock_irqsave(&hw->lock, flags);
-
- val = __raw_readl(hw->regs + USI_CNT);
-
- if (lsb)
- val |= LSB;
- else
- val &= ~LSB;
- __raw_writel(val, hw->regs + USI_CNT);
-
- spin_unlock_irqrestore(&hw->lock, flags);
-}
-
-static void nuc900_set_sleep(struct nuc900_spi *hw, unsigned int sleep)
-{
- unsigned int val;
- unsigned long flags;
-
- spin_lock_irqsave(&hw->lock, flags);
-
- val = __raw_readl(hw->regs + USI_CNT) & ~SLEEP;
-
- if (sleep)
- val |= (sleep << 12);
-
- __raw_writel(val, hw->regs + USI_CNT);
-
- spin_unlock_irqrestore(&hw->lock, flags);
-}
-
-static void nuc900_enable_int(struct nuc900_spi *hw)
-{
- unsigned int val;
- unsigned long flags;
-
- spin_lock_irqsave(&hw->lock, flags);
-
- val = __raw_readl(hw->regs + USI_CNT);
-
- val |= ENINT;
-
- __raw_writel(val, hw->regs + USI_CNT);
-
- spin_unlock_irqrestore(&hw->lock, flags);
-}
-
-static void nuc900_set_divider(struct nuc900_spi *hw)
-{
- __raw_writel(hw->pdata->divider, hw->regs + USI_DIV);
-}
-
-static void nuc900_init_spi(struct nuc900_spi *hw)
-{
- clk_enable(hw->clk);
- spin_lock_init(&hw->lock);
-
- nuc900_tx_edge(hw, hw->pdata->txneg);
- nuc900_rx_edge(hw, hw->pdata->rxneg);
- nuc900_send_first(hw, hw->pdata->lsb);
- nuc900_set_sleep(hw, hw->pdata->sleep);
- nuc900_spi_setup_txbitlen(hw, hw->pdata->txbitlen);
- nuc900_spi_setup_txnum(hw, hw->pdata->txnum);
- nuc900_set_divider(hw);
- nuc900_enable_int(hw);
-}
-
-static int nuc900_spi_probe(struct platform_device *pdev)
-{
- struct nuc900_spi *hw;
- struct spi_master *master;
- struct resource *res;
- int err = 0;
-
- master = spi_alloc_master(&pdev->dev, sizeof(struct nuc900_spi));
- if (master == NULL) {
- dev_err(&pdev->dev, "No memory for spi_master\n");
- return -ENOMEM;
- }
-
- hw = spi_master_get_devdata(master);
- hw->master = master;
- hw->pdata = dev_get_platdata(&pdev->dev);
-
- if (hw->pdata == NULL) {
- dev_err(&pdev->dev, "No platform data supplied\n");
- err = -ENOENT;
- goto err_pdata;
- }
-
- platform_set_drvdata(pdev, hw);
- init_completion(&hw->done);
-
- master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
- if (hw->pdata->lsb)
- master->mode_bits |= SPI_LSB_FIRST;
- master->num_chipselect = hw->pdata->num_cs;
- master->bus_num = hw->pdata->bus_num;
- hw->bitbang.master = hw->master;
- hw->bitbang.chipselect = nuc900_spi_chipsel;
- hw->bitbang.txrx_bufs = nuc900_spi_txrx;
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- hw->regs = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(hw->regs)) {
- err = PTR_ERR(hw->regs);
- goto err_pdata;
- }
-
- hw->irq = platform_get_irq(pdev, 0);
- if (hw->irq < 0) {
- dev_err(&pdev->dev, "No IRQ specified\n");
- err = -ENOENT;
- goto err_pdata;
- }
-
- err = devm_request_irq(&pdev->dev, hw->irq, nuc900_spi_irq, 0,
- pdev->name, hw);
- if (err) {
- dev_err(&pdev->dev, "Cannot claim IRQ\n");
- goto err_pdata;
- }
-
- hw->clk = devm_clk_get(&pdev->dev, "spi");
- if (IS_ERR(hw->clk)) {
- dev_err(&pdev->dev, "No clock for device\n");
- err = PTR_ERR(hw->clk);
- goto err_pdata;
- }
-
- mfp_set_groupg(&pdev->dev, NULL);
- nuc900_init_spi(hw);
-
- err = spi_bitbang_start(&hw->bitbang);
- if (err) {
- dev_err(&pdev->dev, "Failed to register SPI master\n");
- goto err_register;
- }
-
- return 0;
-
-err_register:
- clk_disable(hw->clk);
-err_pdata:
- spi_master_put(hw->master);
- return err;
-}
-
-static int nuc900_spi_remove(struct platform_device *dev)
-{
- struct nuc900_spi *hw = platform_get_drvdata(dev);
-
- spi_bitbang_stop(&hw->bitbang);
- clk_disable(hw->clk);
- spi_master_put(hw->master);
- return 0;
-}
-
-static struct platform_driver nuc900_spi_driver = {
- .probe = nuc900_spi_probe,
- .remove = nuc900_spi_remove,
- .driver = {
- .name = "nuc900-spi",
- },
-};
-module_platform_driver(nuc900_spi_driver);
-
-MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
-MODULE_DESCRIPTION("nuc900 spi driver!");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:nuc900-spi");
projects / openwrt / staging / blogic.git / commitdiff