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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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5bc486156d
Use devm_platform_get_and_ioremap_resource() to simplify code instead of platform_get_resource() and devm_ioremap_resource(). This also gets the resource that the following code uses. Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com> Link: https://lore.kernel.org/r/1589185530-28170-2-git-send-email-hayashi.kunihiko@socionext.com Signed-off-by: Mark Brown <broonie@kernel.org>
801 lines
19 KiB
C
801 lines
19 KiB
C
// SPDX-License-Identifier: GPL-2.0
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// spi-uniphier.c - Socionext UniPhier SPI controller driver
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// Copyright 2012 Panasonic Corporation
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// Copyright 2016-2018 Socionext Inc.
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#include <linux/kernel.h>
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#include <linux/bitfield.h>
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#include <linux/bitops.h>
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#include <linux/clk.h>
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#include <linux/delay.h>
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#include <linux/dmaengine.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/module.h>
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#include <linux/platform_device.h>
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#include <linux/spi/spi.h>
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#include <asm/unaligned.h>
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#define SSI_TIMEOUT_MS 2000
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#define SSI_POLL_TIMEOUT_US 200
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#define SSI_MAX_CLK_DIVIDER 254
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#define SSI_MIN_CLK_DIVIDER 4
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struct uniphier_spi_priv {
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void __iomem *base;
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dma_addr_t base_dma_addr;
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struct clk *clk;
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struct spi_master *master;
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struct completion xfer_done;
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int error;
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unsigned int tx_bytes;
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unsigned int rx_bytes;
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const u8 *tx_buf;
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u8 *rx_buf;
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atomic_t dma_busy;
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bool is_save_param;
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u8 bits_per_word;
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u16 mode;
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u32 speed_hz;
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};
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#define SSI_CTL 0x00
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#define SSI_CTL_EN BIT(0)
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#define SSI_CKS 0x04
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#define SSI_CKS_CKRAT_MASK GENMASK(7, 0)
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#define SSI_CKS_CKPHS BIT(14)
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#define SSI_CKS_CKINIT BIT(13)
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#define SSI_CKS_CKDLY BIT(12)
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#define SSI_TXWDS 0x08
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#define SSI_TXWDS_WDLEN_MASK GENMASK(13, 8)
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#define SSI_TXWDS_TDTF_MASK GENMASK(7, 6)
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#define SSI_TXWDS_DTLEN_MASK GENMASK(5, 0)
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#define SSI_RXWDS 0x0c
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#define SSI_RXWDS_DTLEN_MASK GENMASK(5, 0)
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#define SSI_FPS 0x10
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#define SSI_FPS_FSPOL BIT(15)
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#define SSI_FPS_FSTRT BIT(14)
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#define SSI_SR 0x14
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#define SSI_SR_BUSY BIT(7)
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#define SSI_SR_RNE BIT(0)
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#define SSI_IE 0x18
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#define SSI_IE_TCIE BIT(4)
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#define SSI_IE_RCIE BIT(3)
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#define SSI_IE_TXRE BIT(2)
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#define SSI_IE_RXRE BIT(1)
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#define SSI_IE_RORIE BIT(0)
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#define SSI_IE_ALL_MASK GENMASK(4, 0)
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#define SSI_IS 0x1c
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#define SSI_IS_RXRS BIT(9)
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#define SSI_IS_RCID BIT(3)
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#define SSI_IS_RORID BIT(0)
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#define SSI_IC 0x1c
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#define SSI_IC_TCIC BIT(4)
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#define SSI_IC_RCIC BIT(3)
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#define SSI_IC_RORIC BIT(0)
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#define SSI_FC 0x20
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#define SSI_FC_TXFFL BIT(12)
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#define SSI_FC_TXFTH_MASK GENMASK(11, 8)
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#define SSI_FC_RXFFL BIT(4)
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#define SSI_FC_RXFTH_MASK GENMASK(3, 0)
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#define SSI_TXDR 0x24
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#define SSI_RXDR 0x24
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#define SSI_FIFO_DEPTH 8U
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#define SSI_FIFO_BURST_NUM 1
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#define SSI_DMA_RX_BUSY BIT(1)
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#define SSI_DMA_TX_BUSY BIT(0)
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static inline unsigned int bytes_per_word(unsigned int bits)
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{
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return bits <= 8 ? 1 : (bits <= 16 ? 2 : 4);
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}
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static inline void uniphier_spi_irq_enable(struct uniphier_spi_priv *priv,
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u32 mask)
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{
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u32 val;
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val = readl(priv->base + SSI_IE);
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val |= mask;
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writel(val, priv->base + SSI_IE);
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}
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static inline void uniphier_spi_irq_disable(struct uniphier_spi_priv *priv,
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u32 mask)
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{
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u32 val;
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val = readl(priv->base + SSI_IE);
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val &= ~mask;
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writel(val, priv->base + SSI_IE);
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}
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static void uniphier_spi_set_mode(struct spi_device *spi)
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{
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struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
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u32 val1, val2;
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/*
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* clock setting
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* CKPHS capture timing. 0:rising edge, 1:falling edge
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* CKINIT clock initial level. 0:low, 1:high
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* CKDLY clock delay. 0:no delay, 1:delay depending on FSTRT
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* (FSTRT=0: 1 clock, FSTRT=1: 0.5 clock)
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*
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* frame setting
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* FSPOL frame signal porarity. 0: low, 1: high
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* FSTRT start frame timing
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* 0: rising edge of clock, 1: falling edge of clock
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*/
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switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
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case SPI_MODE_0:
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/* CKPHS=1, CKINIT=0, CKDLY=1, FSTRT=0 */
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val1 = SSI_CKS_CKPHS | SSI_CKS_CKDLY;
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val2 = 0;
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break;
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case SPI_MODE_1:
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/* CKPHS=0, CKINIT=0, CKDLY=0, FSTRT=1 */
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val1 = 0;
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val2 = SSI_FPS_FSTRT;
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break;
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case SPI_MODE_2:
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/* CKPHS=0, CKINIT=1, CKDLY=1, FSTRT=1 */
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val1 = SSI_CKS_CKINIT | SSI_CKS_CKDLY;
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val2 = SSI_FPS_FSTRT;
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break;
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case SPI_MODE_3:
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/* CKPHS=1, CKINIT=1, CKDLY=0, FSTRT=0 */
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val1 = SSI_CKS_CKPHS | SSI_CKS_CKINIT;
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val2 = 0;
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break;
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}
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if (!(spi->mode & SPI_CS_HIGH))
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val2 |= SSI_FPS_FSPOL;
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writel(val1, priv->base + SSI_CKS);
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writel(val2, priv->base + SSI_FPS);
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val1 = 0;
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if (spi->mode & SPI_LSB_FIRST)
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val1 |= FIELD_PREP(SSI_TXWDS_TDTF_MASK, 1);
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writel(val1, priv->base + SSI_TXWDS);
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writel(val1, priv->base + SSI_RXWDS);
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}
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static void uniphier_spi_set_transfer_size(struct spi_device *spi, int size)
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{
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struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
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u32 val;
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val = readl(priv->base + SSI_TXWDS);
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val &= ~(SSI_TXWDS_WDLEN_MASK | SSI_TXWDS_DTLEN_MASK);
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val |= FIELD_PREP(SSI_TXWDS_WDLEN_MASK, size);
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val |= FIELD_PREP(SSI_TXWDS_DTLEN_MASK, size);
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writel(val, priv->base + SSI_TXWDS);
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val = readl(priv->base + SSI_RXWDS);
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val &= ~SSI_RXWDS_DTLEN_MASK;
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val |= FIELD_PREP(SSI_RXWDS_DTLEN_MASK, size);
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writel(val, priv->base + SSI_RXWDS);
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}
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static void uniphier_spi_set_baudrate(struct spi_device *spi,
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unsigned int speed)
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{
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struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
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u32 val, ckdiv;
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/*
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* the supported rates are even numbers from 4 to 254. (4,6,8...254)
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* round up as we look for equal or less speed
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*/
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ckdiv = DIV_ROUND_UP(clk_get_rate(priv->clk), speed);
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ckdiv = round_up(ckdiv, 2);
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val = readl(priv->base + SSI_CKS);
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val &= ~SSI_CKS_CKRAT_MASK;
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val |= ckdiv & SSI_CKS_CKRAT_MASK;
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writel(val, priv->base + SSI_CKS);
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}
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static void uniphier_spi_setup_transfer(struct spi_device *spi,
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struct spi_transfer *t)
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{
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struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
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u32 val;
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priv->error = 0;
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priv->tx_buf = t->tx_buf;
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priv->rx_buf = t->rx_buf;
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priv->tx_bytes = priv->rx_bytes = t->len;
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if (!priv->is_save_param || priv->mode != spi->mode) {
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uniphier_spi_set_mode(spi);
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priv->mode = spi->mode;
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priv->is_save_param = false;
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}
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if (!priv->is_save_param || priv->bits_per_word != t->bits_per_word) {
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uniphier_spi_set_transfer_size(spi, t->bits_per_word);
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priv->bits_per_word = t->bits_per_word;
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}
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if (!priv->is_save_param || priv->speed_hz != t->speed_hz) {
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uniphier_spi_set_baudrate(spi, t->speed_hz);
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priv->speed_hz = t->speed_hz;
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}
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priv->is_save_param = true;
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/* reset FIFOs */
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val = SSI_FC_TXFFL | SSI_FC_RXFFL;
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writel(val, priv->base + SSI_FC);
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}
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static void uniphier_spi_send(struct uniphier_spi_priv *priv)
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{
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int wsize;
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u32 val = 0;
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wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
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priv->tx_bytes -= wsize;
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if (priv->tx_buf) {
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switch (wsize) {
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case 1:
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val = *priv->tx_buf;
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break;
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case 2:
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val = get_unaligned_le16(priv->tx_buf);
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break;
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case 4:
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val = get_unaligned_le32(priv->tx_buf);
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break;
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}
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priv->tx_buf += wsize;
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}
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writel(val, priv->base + SSI_TXDR);
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}
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static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
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{
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int rsize;
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u32 val;
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rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes);
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priv->rx_bytes -= rsize;
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val = readl(priv->base + SSI_RXDR);
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if (priv->rx_buf) {
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switch (rsize) {
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case 1:
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*priv->rx_buf = val;
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break;
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case 2:
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put_unaligned_le16(val, priv->rx_buf);
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break;
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case 4:
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put_unaligned_le32(val, priv->rx_buf);
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break;
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}
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priv->rx_buf += rsize;
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}
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}
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static void uniphier_spi_set_fifo_threshold(struct uniphier_spi_priv *priv,
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unsigned int threshold)
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{
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u32 val;
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val = readl(priv->base + SSI_FC);
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val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
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val |= FIELD_PREP(SSI_FC_TXFTH_MASK, SSI_FIFO_DEPTH - threshold);
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val |= FIELD_PREP(SSI_FC_RXFTH_MASK, threshold);
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writel(val, priv->base + SSI_FC);
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}
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static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
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{
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unsigned int fifo_threshold, fill_words;
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unsigned int bpw = bytes_per_word(priv->bits_per_word);
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fifo_threshold = DIV_ROUND_UP(priv->rx_bytes, bpw);
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fifo_threshold = min(fifo_threshold, SSI_FIFO_DEPTH);
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uniphier_spi_set_fifo_threshold(priv, fifo_threshold);
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fill_words = fifo_threshold -
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DIV_ROUND_UP(priv->rx_bytes - priv->tx_bytes, bpw);
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while (fill_words--)
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uniphier_spi_send(priv);
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}
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static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
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{
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struct uniphier_spi_priv *priv = spi_master_get_devdata(spi->master);
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u32 val;
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val = readl(priv->base + SSI_FPS);
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if (enable)
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val |= SSI_FPS_FSPOL;
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else
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val &= ~SSI_FPS_FSPOL;
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writel(val, priv->base + SSI_FPS);
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}
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static bool uniphier_spi_can_dma(struct spi_master *master,
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struct spi_device *spi,
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struct spi_transfer *t)
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{
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struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
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unsigned int bpw = bytes_per_word(priv->bits_per_word);
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if ((!master->dma_tx && !master->dma_rx)
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|| (!master->dma_tx && t->tx_buf)
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|| (!master->dma_rx && t->rx_buf))
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return false;
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return DIV_ROUND_UP(t->len, bpw) > SSI_FIFO_DEPTH;
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}
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static void uniphier_spi_dma_rxcb(void *data)
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{
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struct spi_master *master = data;
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struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
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int state = atomic_fetch_andnot(SSI_DMA_RX_BUSY, &priv->dma_busy);
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uniphier_spi_irq_disable(priv, SSI_IE_RXRE);
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if (!(state & SSI_DMA_TX_BUSY))
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spi_finalize_current_transfer(master);
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}
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static void uniphier_spi_dma_txcb(void *data)
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{
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struct spi_master *master = data;
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struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
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int state = atomic_fetch_andnot(SSI_DMA_TX_BUSY, &priv->dma_busy);
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uniphier_spi_irq_disable(priv, SSI_IE_TXRE);
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if (!(state & SSI_DMA_RX_BUSY))
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spi_finalize_current_transfer(master);
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}
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static int uniphier_spi_transfer_one_dma(struct spi_master *master,
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struct spi_device *spi,
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struct spi_transfer *t)
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{
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struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
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struct dma_async_tx_descriptor *rxdesc = NULL, *txdesc = NULL;
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int buswidth;
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atomic_set(&priv->dma_busy, 0);
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uniphier_spi_set_fifo_threshold(priv, SSI_FIFO_BURST_NUM);
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if (priv->bits_per_word <= 8)
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buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
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else if (priv->bits_per_word <= 16)
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buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
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else
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buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
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if (priv->rx_buf) {
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struct dma_slave_config rxconf = {
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.direction = DMA_DEV_TO_MEM,
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.src_addr = priv->base_dma_addr + SSI_RXDR,
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.src_addr_width = buswidth,
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.src_maxburst = SSI_FIFO_BURST_NUM,
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};
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dmaengine_slave_config(master->dma_rx, &rxconf);
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rxdesc = dmaengine_prep_slave_sg(
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master->dma_rx,
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t->rx_sg.sgl, t->rx_sg.nents,
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DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
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if (!rxdesc)
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goto out_err_prep;
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rxdesc->callback = uniphier_spi_dma_rxcb;
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rxdesc->callback_param = master;
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uniphier_spi_irq_enable(priv, SSI_IE_RXRE);
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atomic_or(SSI_DMA_RX_BUSY, &priv->dma_busy);
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dmaengine_submit(rxdesc);
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dma_async_issue_pending(master->dma_rx);
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}
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if (priv->tx_buf) {
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struct dma_slave_config txconf = {
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.direction = DMA_MEM_TO_DEV,
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.dst_addr = priv->base_dma_addr + SSI_TXDR,
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.dst_addr_width = buswidth,
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.dst_maxburst = SSI_FIFO_BURST_NUM,
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};
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dmaengine_slave_config(master->dma_tx, &txconf);
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txdesc = dmaengine_prep_slave_sg(
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master->dma_tx,
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t->tx_sg.sgl, t->tx_sg.nents,
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DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
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if (!txdesc)
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goto out_err_prep;
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txdesc->callback = uniphier_spi_dma_txcb;
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txdesc->callback_param = master;
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uniphier_spi_irq_enable(priv, SSI_IE_TXRE);
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atomic_or(SSI_DMA_TX_BUSY, &priv->dma_busy);
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dmaengine_submit(txdesc);
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dma_async_issue_pending(master->dma_tx);
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}
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/* signal that we need to wait for completion */
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return (priv->tx_buf || priv->rx_buf);
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out_err_prep:
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if (rxdesc)
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dmaengine_terminate_sync(master->dma_rx);
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return -EINVAL;
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}
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static int uniphier_spi_transfer_one_irq(struct spi_master *master,
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struct spi_device *spi,
|
|
struct spi_transfer *t)
|
|
{
|
|
struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
|
|
struct device *dev = master->dev.parent;
|
|
unsigned long time_left;
|
|
|
|
reinit_completion(&priv->xfer_done);
|
|
|
|
uniphier_spi_fill_tx_fifo(priv);
|
|
|
|
uniphier_spi_irq_enable(priv, SSI_IE_RCIE | SSI_IE_RORIE);
|
|
|
|
time_left = wait_for_completion_timeout(&priv->xfer_done,
|
|
msecs_to_jiffies(SSI_TIMEOUT_MS));
|
|
|
|
uniphier_spi_irq_disable(priv, SSI_IE_RCIE | SSI_IE_RORIE);
|
|
|
|
if (!time_left) {
|
|
dev_err(dev, "transfer timeout.\n");
|
|
return -ETIMEDOUT;
|
|
}
|
|
|
|
return priv->error;
|
|
}
|
|
|
|
static int uniphier_spi_transfer_one_poll(struct spi_master *master,
|
|
struct spi_device *spi,
|
|
struct spi_transfer *t)
|
|
{
|
|
struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
|
|
int loop = SSI_POLL_TIMEOUT_US * 10;
|
|
|
|
while (priv->tx_bytes) {
|
|
uniphier_spi_fill_tx_fifo(priv);
|
|
|
|
while ((priv->rx_bytes - priv->tx_bytes) > 0) {
|
|
while (!(readl(priv->base + SSI_SR) & SSI_SR_RNE)
|
|
&& loop--)
|
|
ndelay(100);
|
|
|
|
if (loop == -1)
|
|
goto irq_transfer;
|
|
|
|
uniphier_spi_recv(priv);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
|
|
irq_transfer:
|
|
return uniphier_spi_transfer_one_irq(master, spi, t);
|
|
}
|
|
|
|
static int uniphier_spi_transfer_one(struct spi_master *master,
|
|
struct spi_device *spi,
|
|
struct spi_transfer *t)
|
|
{
|
|
struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
|
|
unsigned long threshold;
|
|
bool use_dma;
|
|
|
|
/* Terminate and return success for 0 byte length transfer */
|
|
if (!t->len)
|
|
return 0;
|
|
|
|
uniphier_spi_setup_transfer(spi, t);
|
|
|
|
use_dma = master->can_dma ? master->can_dma(master, spi, t) : false;
|
|
if (use_dma)
|
|
return uniphier_spi_transfer_one_dma(master, spi, t);
|
|
|
|
/*
|
|
* If the transfer operation will take longer than
|
|
* SSI_POLL_TIMEOUT_US, it should use irq.
|
|
*/
|
|
threshold = DIV_ROUND_UP(SSI_POLL_TIMEOUT_US * priv->speed_hz,
|
|
USEC_PER_SEC * BITS_PER_BYTE);
|
|
if (t->len > threshold)
|
|
return uniphier_spi_transfer_one_irq(master, spi, t);
|
|
else
|
|
return uniphier_spi_transfer_one_poll(master, spi, t);
|
|
}
|
|
|
|
static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
|
|
{
|
|
struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
|
|
|
|
writel(SSI_CTL_EN, priv->base + SSI_CTL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int uniphier_spi_unprepare_transfer_hardware(struct spi_master *master)
|
|
{
|
|
struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
|
|
|
|
writel(0, priv->base + SSI_CTL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void uniphier_spi_handle_err(struct spi_master *master,
|
|
struct spi_message *msg)
|
|
{
|
|
struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
|
|
u32 val;
|
|
|
|
/* stop running spi transfer */
|
|
writel(0, priv->base + SSI_CTL);
|
|
|
|
/* reset FIFOs */
|
|
val = SSI_FC_TXFFL | SSI_FC_RXFFL;
|
|
writel(val, priv->base + SSI_FC);
|
|
|
|
uniphier_spi_irq_disable(priv, SSI_IE_ALL_MASK);
|
|
|
|
if (atomic_read(&priv->dma_busy) & SSI_DMA_TX_BUSY) {
|
|
dmaengine_terminate_async(master->dma_tx);
|
|
atomic_andnot(SSI_DMA_TX_BUSY, &priv->dma_busy);
|
|
}
|
|
|
|
if (atomic_read(&priv->dma_busy) & SSI_DMA_RX_BUSY) {
|
|
dmaengine_terminate_async(master->dma_rx);
|
|
atomic_andnot(SSI_DMA_RX_BUSY, &priv->dma_busy);
|
|
}
|
|
}
|
|
|
|
static irqreturn_t uniphier_spi_handler(int irq, void *dev_id)
|
|
{
|
|
struct uniphier_spi_priv *priv = dev_id;
|
|
u32 val, stat;
|
|
|
|
stat = readl(priv->base + SSI_IS);
|
|
val = SSI_IC_TCIC | SSI_IC_RCIC | SSI_IC_RORIC;
|
|
writel(val, priv->base + SSI_IC);
|
|
|
|
/* rx fifo overrun */
|
|
if (stat & SSI_IS_RORID) {
|
|
priv->error = -EIO;
|
|
goto done;
|
|
}
|
|
|
|
/* rx complete */
|
|
if ((stat & SSI_IS_RCID) && (stat & SSI_IS_RXRS)) {
|
|
while ((readl(priv->base + SSI_SR) & SSI_SR_RNE) &&
|
|
(priv->rx_bytes - priv->tx_bytes) > 0)
|
|
uniphier_spi_recv(priv);
|
|
|
|
if ((readl(priv->base + SSI_SR) & SSI_SR_RNE) ||
|
|
(priv->rx_bytes != priv->tx_bytes)) {
|
|
priv->error = -EIO;
|
|
goto done;
|
|
} else if (priv->rx_bytes == 0)
|
|
goto done;
|
|
|
|
/* next tx transfer */
|
|
uniphier_spi_fill_tx_fifo(priv);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
return IRQ_NONE;
|
|
|
|
done:
|
|
complete(&priv->xfer_done);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int uniphier_spi_probe(struct platform_device *pdev)
|
|
{
|
|
struct uniphier_spi_priv *priv;
|
|
struct spi_master *master;
|
|
struct resource *res;
|
|
struct dma_slave_caps caps;
|
|
u32 dma_tx_burst = 0, dma_rx_burst = 0;
|
|
unsigned long clk_rate;
|
|
int irq;
|
|
int ret;
|
|
|
|
master = spi_alloc_master(&pdev->dev, sizeof(*priv));
|
|
if (!master)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, master);
|
|
|
|
priv = spi_master_get_devdata(master);
|
|
priv->master = master;
|
|
priv->is_save_param = false;
|
|
|
|
priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
|
|
if (IS_ERR(priv->base)) {
|
|
ret = PTR_ERR(priv->base);
|
|
goto out_master_put;
|
|
}
|
|
priv->base_dma_addr = res->start;
|
|
|
|
priv->clk = devm_clk_get(&pdev->dev, NULL);
|
|
if (IS_ERR(priv->clk)) {
|
|
dev_err(&pdev->dev, "failed to get clock\n");
|
|
ret = PTR_ERR(priv->clk);
|
|
goto out_master_put;
|
|
}
|
|
|
|
ret = clk_prepare_enable(priv->clk);
|
|
if (ret)
|
|
goto out_master_put;
|
|
|
|
irq = platform_get_irq(pdev, 0);
|
|
if (irq < 0) {
|
|
ret = irq;
|
|
goto out_disable_clk;
|
|
}
|
|
|
|
ret = devm_request_irq(&pdev->dev, irq, uniphier_spi_handler,
|
|
0, "uniphier-spi", priv);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "failed to request IRQ\n");
|
|
goto out_disable_clk;
|
|
}
|
|
|
|
init_completion(&priv->xfer_done);
|
|
|
|
clk_rate = clk_get_rate(priv->clk);
|
|
|
|
master->max_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MIN_CLK_DIVIDER);
|
|
master->min_speed_hz = DIV_ROUND_UP(clk_rate, SSI_MAX_CLK_DIVIDER);
|
|
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
|
|
master->dev.of_node = pdev->dev.of_node;
|
|
master->bus_num = pdev->id;
|
|
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
|
|
|
|
master->set_cs = uniphier_spi_set_cs;
|
|
master->transfer_one = uniphier_spi_transfer_one;
|
|
master->prepare_transfer_hardware
|
|
= uniphier_spi_prepare_transfer_hardware;
|
|
master->unprepare_transfer_hardware
|
|
= uniphier_spi_unprepare_transfer_hardware;
|
|
master->handle_err = uniphier_spi_handle_err;
|
|
master->can_dma = uniphier_spi_can_dma;
|
|
|
|
master->num_chipselect = 1;
|
|
master->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
|
|
|
|
master->dma_tx = dma_request_chan(&pdev->dev, "tx");
|
|
if (IS_ERR_OR_NULL(master->dma_tx)) {
|
|
if (PTR_ERR(master->dma_tx) == -EPROBE_DEFER) {
|
|
ret = -EPROBE_DEFER;
|
|
goto out_disable_clk;
|
|
}
|
|
master->dma_tx = NULL;
|
|
dma_tx_burst = INT_MAX;
|
|
} else {
|
|
ret = dma_get_slave_caps(master->dma_tx, &caps);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "failed to get TX DMA capacities: %d\n",
|
|
ret);
|
|
goto out_disable_clk;
|
|
}
|
|
dma_tx_burst = caps.max_burst;
|
|
}
|
|
|
|
master->dma_rx = dma_request_chan(&pdev->dev, "rx");
|
|
if (IS_ERR_OR_NULL(master->dma_rx)) {
|
|
if (PTR_ERR(master->dma_rx) == -EPROBE_DEFER) {
|
|
ret = -EPROBE_DEFER;
|
|
goto out_disable_clk;
|
|
}
|
|
master->dma_rx = NULL;
|
|
dma_rx_burst = INT_MAX;
|
|
} else {
|
|
ret = dma_get_slave_caps(master->dma_rx, &caps);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "failed to get RX DMA capacities: %d\n",
|
|
ret);
|
|
goto out_disable_clk;
|
|
}
|
|
dma_rx_burst = caps.max_burst;
|
|
}
|
|
|
|
master->max_dma_len = min(dma_tx_burst, dma_rx_burst);
|
|
|
|
ret = devm_spi_register_master(&pdev->dev, master);
|
|
if (ret)
|
|
goto out_disable_clk;
|
|
|
|
return 0;
|
|
|
|
out_disable_clk:
|
|
clk_disable_unprepare(priv->clk);
|
|
|
|
out_master_put:
|
|
spi_master_put(master);
|
|
return ret;
|
|
}
|
|
|
|
static int uniphier_spi_remove(struct platform_device *pdev)
|
|
{
|
|
struct uniphier_spi_priv *priv = platform_get_drvdata(pdev);
|
|
|
|
if (priv->master->dma_tx)
|
|
dma_release_channel(priv->master->dma_tx);
|
|
if (priv->master->dma_rx)
|
|
dma_release_channel(priv->master->dma_rx);
|
|
|
|
clk_disable_unprepare(priv->clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id uniphier_spi_match[] = {
|
|
{ .compatible = "socionext,uniphier-scssi" },
|
|
{ /* sentinel */ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, uniphier_spi_match);
|
|
|
|
static struct platform_driver uniphier_spi_driver = {
|
|
.probe = uniphier_spi_probe,
|
|
.remove = uniphier_spi_remove,
|
|
.driver = {
|
|
.name = "uniphier-spi",
|
|
.of_match_table = uniphier_spi_match,
|
|
},
|
|
};
|
|
module_platform_driver(uniphier_spi_driver);
|
|
|
|
MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
|
|
MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
|
|
MODULE_DESCRIPTION("Socionext UniPhier SPI controller driver");
|
|
MODULE_LICENSE("GPL v2");
|