forked from Minki/linux
940f3bbf3d
If SPI is used for periodic polling any sensor, significant delays sometimes appear. Switching on module clocks during resume lead to delays. Enabling autosuspend mode causes the controller to not suspend between SPI transfers and the delays disappear. Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com> Link: https://lore.kernel.org/r/20201016085014.31667-1-al.kochet@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
937 lines
23 KiB
C
937 lines
23 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
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* Author: Addy Ke <addy.ke@rock-chips.com>
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*/
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#include <linux/clk.h>
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#include <linux/dmaengine.h>
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#include <linux/interrupt.h>
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/pinctrl/consumer.h>
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#include <linux/platform_device.h>
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#include <linux/spi/spi.h>
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#include <linux/pm_runtime.h>
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#include <linux/scatterlist.h>
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#define DRIVER_NAME "rockchip-spi"
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#define ROCKCHIP_SPI_CLR_BITS(reg, bits) \
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writel_relaxed(readl_relaxed(reg) & ~(bits), reg)
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#define ROCKCHIP_SPI_SET_BITS(reg, bits) \
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writel_relaxed(readl_relaxed(reg) | (bits), reg)
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/* SPI register offsets */
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#define ROCKCHIP_SPI_CTRLR0 0x0000
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#define ROCKCHIP_SPI_CTRLR1 0x0004
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#define ROCKCHIP_SPI_SSIENR 0x0008
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#define ROCKCHIP_SPI_SER 0x000c
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#define ROCKCHIP_SPI_BAUDR 0x0010
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#define ROCKCHIP_SPI_TXFTLR 0x0014
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#define ROCKCHIP_SPI_RXFTLR 0x0018
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#define ROCKCHIP_SPI_TXFLR 0x001c
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#define ROCKCHIP_SPI_RXFLR 0x0020
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#define ROCKCHIP_SPI_SR 0x0024
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#define ROCKCHIP_SPI_IPR 0x0028
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#define ROCKCHIP_SPI_IMR 0x002c
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#define ROCKCHIP_SPI_ISR 0x0030
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#define ROCKCHIP_SPI_RISR 0x0034
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#define ROCKCHIP_SPI_ICR 0x0038
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#define ROCKCHIP_SPI_DMACR 0x003c
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#define ROCKCHIP_SPI_DMATDLR 0x0040
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#define ROCKCHIP_SPI_DMARDLR 0x0044
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#define ROCKCHIP_SPI_VERSION 0x0048
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#define ROCKCHIP_SPI_TXDR 0x0400
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#define ROCKCHIP_SPI_RXDR 0x0800
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/* Bit fields in CTRLR0 */
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#define CR0_DFS_OFFSET 0
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#define CR0_DFS_4BIT 0x0
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#define CR0_DFS_8BIT 0x1
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#define CR0_DFS_16BIT 0x2
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#define CR0_CFS_OFFSET 2
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#define CR0_SCPH_OFFSET 6
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#define CR0_SCPOL_OFFSET 7
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#define CR0_CSM_OFFSET 8
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#define CR0_CSM_KEEP 0x0
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/* ss_n be high for half sclk_out cycles */
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#define CR0_CSM_HALF 0X1
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/* ss_n be high for one sclk_out cycle */
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#define CR0_CSM_ONE 0x2
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/* ss_n to sclk_out delay */
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#define CR0_SSD_OFFSET 10
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/*
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* The period between ss_n active and
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* sclk_out active is half sclk_out cycles
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*/
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#define CR0_SSD_HALF 0x0
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/*
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* The period between ss_n active and
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* sclk_out active is one sclk_out cycle
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*/
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#define CR0_SSD_ONE 0x1
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#define CR0_EM_OFFSET 11
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#define CR0_EM_LITTLE 0x0
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#define CR0_EM_BIG 0x1
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#define CR0_FBM_OFFSET 12
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#define CR0_FBM_MSB 0x0
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#define CR0_FBM_LSB 0x1
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#define CR0_BHT_OFFSET 13
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#define CR0_BHT_16BIT 0x0
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#define CR0_BHT_8BIT 0x1
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#define CR0_RSD_OFFSET 14
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#define CR0_RSD_MAX 0x3
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#define CR0_FRF_OFFSET 16
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#define CR0_FRF_SPI 0x0
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#define CR0_FRF_SSP 0x1
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#define CR0_FRF_MICROWIRE 0x2
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#define CR0_XFM_OFFSET 18
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#define CR0_XFM_MASK (0x03 << SPI_XFM_OFFSET)
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#define CR0_XFM_TR 0x0
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#define CR0_XFM_TO 0x1
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#define CR0_XFM_RO 0x2
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#define CR0_OPM_OFFSET 20
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#define CR0_OPM_MASTER 0x0
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#define CR0_OPM_SLAVE 0x1
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#define CR0_MTM_OFFSET 0x21
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/* Bit fields in SER, 2bit */
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#define SER_MASK 0x3
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/* Bit fields in BAUDR */
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#define BAUDR_SCKDV_MIN 2
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#define BAUDR_SCKDV_MAX 65534
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/* Bit fields in SR, 5bit */
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#define SR_MASK 0x1f
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#define SR_BUSY (1 << 0)
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#define SR_TF_FULL (1 << 1)
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#define SR_TF_EMPTY (1 << 2)
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#define SR_RF_EMPTY (1 << 3)
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#define SR_RF_FULL (1 << 4)
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/* Bit fields in ISR, IMR, ISR, RISR, 5bit */
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#define INT_MASK 0x1f
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#define INT_TF_EMPTY (1 << 0)
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#define INT_TF_OVERFLOW (1 << 1)
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#define INT_RF_UNDERFLOW (1 << 2)
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#define INT_RF_OVERFLOW (1 << 3)
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#define INT_RF_FULL (1 << 4)
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/* Bit fields in ICR, 4bit */
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#define ICR_MASK 0x0f
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#define ICR_ALL (1 << 0)
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#define ICR_RF_UNDERFLOW (1 << 1)
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#define ICR_RF_OVERFLOW (1 << 2)
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#define ICR_TF_OVERFLOW (1 << 3)
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/* Bit fields in DMACR */
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#define RF_DMA_EN (1 << 0)
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#define TF_DMA_EN (1 << 1)
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/* Driver state flags */
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#define RXDMA (1 << 0)
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#define TXDMA (1 << 1)
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/* sclk_out: spi master internal logic in rk3x can support 50Mhz */
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#define MAX_SCLK_OUT 50000000U
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/*
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* SPI_CTRLR1 is 16-bits, so we should support lengths of 0xffff + 1. However,
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* the controller seems to hang when given 0x10000, so stick with this for now.
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*/
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#define ROCKCHIP_SPI_MAX_TRANLEN 0xffff
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#define ROCKCHIP_SPI_MAX_CS_NUM 2
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#define ROCKCHIP_SPI_VER2_TYPE1 0x05EC0002
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#define ROCKCHIP_SPI_VER2_TYPE2 0x00110002
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#define ROCKCHIP_AUTOSUSPEND_TIMEOUT 2000
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struct rockchip_spi {
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struct device *dev;
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struct clk *spiclk;
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struct clk *apb_pclk;
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void __iomem *regs;
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dma_addr_t dma_addr_rx;
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dma_addr_t dma_addr_tx;
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const void *tx;
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void *rx;
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unsigned int tx_left;
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unsigned int rx_left;
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atomic_t state;
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/*depth of the FIFO buffer */
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u32 fifo_len;
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/* frequency of spiclk */
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u32 freq;
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u8 n_bytes;
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u8 rsd;
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bool cs_asserted[ROCKCHIP_SPI_MAX_CS_NUM];
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bool slave_abort;
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};
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static inline void spi_enable_chip(struct rockchip_spi *rs, bool enable)
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{
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writel_relaxed((enable ? 1U : 0U), rs->regs + ROCKCHIP_SPI_SSIENR);
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}
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static inline void wait_for_idle(struct rockchip_spi *rs)
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{
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unsigned long timeout = jiffies + msecs_to_jiffies(5);
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do {
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if (!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY))
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return;
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} while (!time_after(jiffies, timeout));
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dev_warn(rs->dev, "spi controller is in busy state!\n");
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}
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static u32 get_fifo_len(struct rockchip_spi *rs)
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{
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u32 ver;
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ver = readl_relaxed(rs->regs + ROCKCHIP_SPI_VERSION);
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switch (ver) {
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case ROCKCHIP_SPI_VER2_TYPE1:
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case ROCKCHIP_SPI_VER2_TYPE2:
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return 64;
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default:
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return 32;
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}
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}
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static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
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{
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struct spi_controller *ctlr = spi->controller;
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struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
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bool cs_asserted = !enable;
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/* Return immediately for no-op */
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if (cs_asserted == rs->cs_asserted[spi->chip_select])
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return;
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if (cs_asserted) {
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/* Keep things powered as long as CS is asserted */
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pm_runtime_get_sync(rs->dev);
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ROCKCHIP_SPI_SET_BITS(rs->regs + ROCKCHIP_SPI_SER,
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BIT(spi->chip_select));
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} else {
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ROCKCHIP_SPI_CLR_BITS(rs->regs + ROCKCHIP_SPI_SER,
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BIT(spi->chip_select));
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/* Drop reference from when we first asserted CS */
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pm_runtime_put(rs->dev);
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}
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rs->cs_asserted[spi->chip_select] = cs_asserted;
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}
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static void rockchip_spi_handle_err(struct spi_controller *ctlr,
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struct spi_message *msg)
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{
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struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
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/* stop running spi transfer
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* this also flushes both rx and tx fifos
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*/
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spi_enable_chip(rs, false);
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/* make sure all interrupts are masked */
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writel_relaxed(0, rs->regs + ROCKCHIP_SPI_IMR);
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if (atomic_read(&rs->state) & TXDMA)
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dmaengine_terminate_async(ctlr->dma_tx);
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if (atomic_read(&rs->state) & RXDMA)
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dmaengine_terminate_async(ctlr->dma_rx);
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}
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static void rockchip_spi_pio_writer(struct rockchip_spi *rs)
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{
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u32 tx_free = rs->fifo_len - readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFLR);
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u32 words = min(rs->tx_left, tx_free);
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rs->tx_left -= words;
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for (; words; words--) {
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u32 txw;
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if (rs->n_bytes == 1)
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txw = *(u8 *)rs->tx;
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else
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txw = *(u16 *)rs->tx;
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writel_relaxed(txw, rs->regs + ROCKCHIP_SPI_TXDR);
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rs->tx += rs->n_bytes;
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}
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}
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static void rockchip_spi_pio_reader(struct rockchip_spi *rs)
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{
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u32 words = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR);
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u32 rx_left = (rs->rx_left > words) ? rs->rx_left - words : 0;
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/* the hardware doesn't allow us to change fifo threshold
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* level while spi is enabled, so instead make sure to leave
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* enough words in the rx fifo to get the last interrupt
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* exactly when all words have been received
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*/
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if (rx_left) {
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u32 ftl = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFTLR) + 1;
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if (rx_left < ftl) {
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rx_left = ftl;
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words = rs->rx_left - rx_left;
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}
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}
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rs->rx_left = rx_left;
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for (; words; words--) {
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u32 rxw = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
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if (!rs->rx)
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continue;
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if (rs->n_bytes == 1)
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*(u8 *)rs->rx = (u8)rxw;
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else
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*(u16 *)rs->rx = (u16)rxw;
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rs->rx += rs->n_bytes;
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}
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}
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static irqreturn_t rockchip_spi_isr(int irq, void *dev_id)
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{
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struct spi_controller *ctlr = dev_id;
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struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
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if (rs->tx_left)
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rockchip_spi_pio_writer(rs);
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rockchip_spi_pio_reader(rs);
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if (!rs->rx_left) {
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spi_enable_chip(rs, false);
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writel_relaxed(0, rs->regs + ROCKCHIP_SPI_IMR);
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spi_finalize_current_transfer(ctlr);
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}
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return IRQ_HANDLED;
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}
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static int rockchip_spi_prepare_irq(struct rockchip_spi *rs,
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struct spi_transfer *xfer)
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{
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rs->tx = xfer->tx_buf;
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rs->rx = xfer->rx_buf;
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rs->tx_left = rs->tx ? xfer->len / rs->n_bytes : 0;
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rs->rx_left = xfer->len / rs->n_bytes;
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writel_relaxed(INT_RF_FULL, rs->regs + ROCKCHIP_SPI_IMR);
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spi_enable_chip(rs, true);
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if (rs->tx_left)
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rockchip_spi_pio_writer(rs);
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/* 1 means the transfer is in progress */
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return 1;
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}
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static void rockchip_spi_dma_rxcb(void *data)
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{
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struct spi_controller *ctlr = data;
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struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
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int state = atomic_fetch_andnot(RXDMA, &rs->state);
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if (state & TXDMA && !rs->slave_abort)
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return;
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spi_enable_chip(rs, false);
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spi_finalize_current_transfer(ctlr);
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}
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static void rockchip_spi_dma_txcb(void *data)
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{
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struct spi_controller *ctlr = data;
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struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
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int state = atomic_fetch_andnot(TXDMA, &rs->state);
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if (state & RXDMA && !rs->slave_abort)
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return;
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/* Wait until the FIFO data completely. */
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wait_for_idle(rs);
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spi_enable_chip(rs, false);
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spi_finalize_current_transfer(ctlr);
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}
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static u32 rockchip_spi_calc_burst_size(u32 data_len)
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{
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u32 i;
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/* burst size: 1, 2, 4, 8 */
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for (i = 1; i < 8; i <<= 1) {
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if (data_len & i)
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break;
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}
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return i;
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}
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static int rockchip_spi_prepare_dma(struct rockchip_spi *rs,
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struct spi_controller *ctlr, struct spi_transfer *xfer)
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{
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struct dma_async_tx_descriptor *rxdesc, *txdesc;
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atomic_set(&rs->state, 0);
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rxdesc = NULL;
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if (xfer->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 = rs->dma_addr_rx,
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.src_addr_width = rs->n_bytes,
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.src_maxburst = rockchip_spi_calc_burst_size(xfer->len /
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rs->n_bytes),
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};
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dmaengine_slave_config(ctlr->dma_rx, &rxconf);
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rxdesc = dmaengine_prep_slave_sg(
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ctlr->dma_rx,
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xfer->rx_sg.sgl, xfer->rx_sg.nents,
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DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
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if (!rxdesc)
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return -EINVAL;
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rxdesc->callback = rockchip_spi_dma_rxcb;
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rxdesc->callback_param = ctlr;
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}
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txdesc = NULL;
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if (xfer->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 = rs->dma_addr_tx,
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.dst_addr_width = rs->n_bytes,
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.dst_maxburst = rs->fifo_len / 4,
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};
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dmaengine_slave_config(ctlr->dma_tx, &txconf);
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txdesc = dmaengine_prep_slave_sg(
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ctlr->dma_tx,
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xfer->tx_sg.sgl, xfer->tx_sg.nents,
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DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
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if (!txdesc) {
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if (rxdesc)
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dmaengine_terminate_sync(ctlr->dma_rx);
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return -EINVAL;
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}
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txdesc->callback = rockchip_spi_dma_txcb;
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txdesc->callback_param = ctlr;
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}
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/* rx must be started before tx due to spi instinct */
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if (rxdesc) {
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atomic_or(RXDMA, &rs->state);
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dmaengine_submit(rxdesc);
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dma_async_issue_pending(ctlr->dma_rx);
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}
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spi_enable_chip(rs, true);
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if (txdesc) {
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atomic_or(TXDMA, &rs->state);
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dmaengine_submit(txdesc);
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dma_async_issue_pending(ctlr->dma_tx);
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}
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/* 1 means the transfer is in progress */
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return 1;
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}
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static void rockchip_spi_config(struct rockchip_spi *rs,
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struct spi_device *spi, struct spi_transfer *xfer,
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bool use_dma, bool slave_mode)
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{
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u32 cr0 = CR0_FRF_SPI << CR0_FRF_OFFSET
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| CR0_BHT_8BIT << CR0_BHT_OFFSET
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| CR0_SSD_ONE << CR0_SSD_OFFSET
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| CR0_EM_BIG << CR0_EM_OFFSET;
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u32 cr1;
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u32 dmacr = 0;
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if (slave_mode)
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cr0 |= CR0_OPM_SLAVE << CR0_OPM_OFFSET;
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rs->slave_abort = false;
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cr0 |= rs->rsd << CR0_RSD_OFFSET;
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cr0 |= (spi->mode & 0x3U) << CR0_SCPH_OFFSET;
|
|
if (spi->mode & SPI_LSB_FIRST)
|
|
cr0 |= CR0_FBM_LSB << CR0_FBM_OFFSET;
|
|
|
|
if (xfer->rx_buf && xfer->tx_buf)
|
|
cr0 |= CR0_XFM_TR << CR0_XFM_OFFSET;
|
|
else if (xfer->rx_buf)
|
|
cr0 |= CR0_XFM_RO << CR0_XFM_OFFSET;
|
|
else if (use_dma)
|
|
cr0 |= CR0_XFM_TO << CR0_XFM_OFFSET;
|
|
|
|
switch (xfer->bits_per_word) {
|
|
case 4:
|
|
cr0 |= CR0_DFS_4BIT << CR0_DFS_OFFSET;
|
|
cr1 = xfer->len - 1;
|
|
break;
|
|
case 8:
|
|
cr0 |= CR0_DFS_8BIT << CR0_DFS_OFFSET;
|
|
cr1 = xfer->len - 1;
|
|
break;
|
|
case 16:
|
|
cr0 |= CR0_DFS_16BIT << CR0_DFS_OFFSET;
|
|
cr1 = xfer->len / 2 - 1;
|
|
break;
|
|
default:
|
|
/* we only whitelist 4, 8 and 16 bit words in
|
|
* ctlr->bits_per_word_mask, so this shouldn't
|
|
* happen
|
|
*/
|
|
unreachable();
|
|
}
|
|
|
|
if (use_dma) {
|
|
if (xfer->tx_buf)
|
|
dmacr |= TF_DMA_EN;
|
|
if (xfer->rx_buf)
|
|
dmacr |= RF_DMA_EN;
|
|
}
|
|
|
|
writel_relaxed(cr0, rs->regs + ROCKCHIP_SPI_CTRLR0);
|
|
writel_relaxed(cr1, rs->regs + ROCKCHIP_SPI_CTRLR1);
|
|
|
|
/* unfortunately setting the fifo threshold level to generate an
|
|
* interrupt exactly when the fifo is full doesn't seem to work,
|
|
* so we need the strict inequality here
|
|
*/
|
|
if (xfer->len < rs->fifo_len)
|
|
writel_relaxed(xfer->len - 1, rs->regs + ROCKCHIP_SPI_RXFTLR);
|
|
else
|
|
writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR);
|
|
|
|
writel_relaxed(rs->fifo_len / 2, rs->regs + ROCKCHIP_SPI_DMATDLR);
|
|
writel_relaxed(rockchip_spi_calc_burst_size(xfer->len / rs->n_bytes) - 1,
|
|
rs->regs + ROCKCHIP_SPI_DMARDLR);
|
|
writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR);
|
|
|
|
/* the hardware only supports an even clock divisor, so
|
|
* round divisor = spiclk / speed up to nearest even number
|
|
* so that the resulting speed is <= the requested speed
|
|
*/
|
|
writel_relaxed(2 * DIV_ROUND_UP(rs->freq, 2 * xfer->speed_hz),
|
|
rs->regs + ROCKCHIP_SPI_BAUDR);
|
|
}
|
|
|
|
static size_t rockchip_spi_max_transfer_size(struct spi_device *spi)
|
|
{
|
|
return ROCKCHIP_SPI_MAX_TRANLEN;
|
|
}
|
|
|
|
static int rockchip_spi_slave_abort(struct spi_controller *ctlr)
|
|
{
|
|
struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
|
|
|
|
rs->slave_abort = true;
|
|
complete(&ctlr->xfer_completion);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int rockchip_spi_transfer_one(
|
|
struct spi_controller *ctlr,
|
|
struct spi_device *spi,
|
|
struct spi_transfer *xfer)
|
|
{
|
|
struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
|
|
bool use_dma;
|
|
|
|
WARN_ON(readl_relaxed(rs->regs + ROCKCHIP_SPI_SSIENR) &&
|
|
(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY));
|
|
|
|
if (!xfer->tx_buf && !xfer->rx_buf) {
|
|
dev_err(rs->dev, "No buffer for transfer\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (xfer->len > ROCKCHIP_SPI_MAX_TRANLEN) {
|
|
dev_err(rs->dev, "Transfer is too long (%d)\n", xfer->len);
|
|
return -EINVAL;
|
|
}
|
|
|
|
rs->n_bytes = xfer->bits_per_word <= 8 ? 1 : 2;
|
|
|
|
use_dma = ctlr->can_dma ? ctlr->can_dma(ctlr, spi, xfer) : false;
|
|
|
|
rockchip_spi_config(rs, spi, xfer, use_dma, ctlr->slave);
|
|
|
|
if (use_dma)
|
|
return rockchip_spi_prepare_dma(rs, ctlr, xfer);
|
|
|
|
return rockchip_spi_prepare_irq(rs, xfer);
|
|
}
|
|
|
|
static bool rockchip_spi_can_dma(struct spi_controller *ctlr,
|
|
struct spi_device *spi,
|
|
struct spi_transfer *xfer)
|
|
{
|
|
struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
|
|
unsigned int bytes_per_word = xfer->bits_per_word <= 8 ? 1 : 2;
|
|
|
|
/* if the numbor of spi words to transfer is less than the fifo
|
|
* length we can just fill the fifo and wait for a single irq,
|
|
* so don't bother setting up dma
|
|
*/
|
|
return xfer->len / bytes_per_word >= rs->fifo_len;
|
|
}
|
|
|
|
static int rockchip_spi_probe(struct platform_device *pdev)
|
|
{
|
|
int ret;
|
|
struct rockchip_spi *rs;
|
|
struct spi_controller *ctlr;
|
|
struct resource *mem;
|
|
struct device_node *np = pdev->dev.of_node;
|
|
u32 rsd_nsecs;
|
|
bool slave_mode;
|
|
|
|
slave_mode = of_property_read_bool(np, "spi-slave");
|
|
|
|
if (slave_mode)
|
|
ctlr = spi_alloc_slave(&pdev->dev,
|
|
sizeof(struct rockchip_spi));
|
|
else
|
|
ctlr = spi_alloc_master(&pdev->dev,
|
|
sizeof(struct rockchip_spi));
|
|
|
|
if (!ctlr)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, ctlr);
|
|
|
|
rs = spi_controller_get_devdata(ctlr);
|
|
ctlr->slave = slave_mode;
|
|
|
|
/* Get basic io resource and map it */
|
|
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
rs->regs = devm_ioremap_resource(&pdev->dev, mem);
|
|
if (IS_ERR(rs->regs)) {
|
|
ret = PTR_ERR(rs->regs);
|
|
goto err_put_ctlr;
|
|
}
|
|
|
|
rs->apb_pclk = devm_clk_get(&pdev->dev, "apb_pclk");
|
|
if (IS_ERR(rs->apb_pclk)) {
|
|
dev_err(&pdev->dev, "Failed to get apb_pclk\n");
|
|
ret = PTR_ERR(rs->apb_pclk);
|
|
goto err_put_ctlr;
|
|
}
|
|
|
|
rs->spiclk = devm_clk_get(&pdev->dev, "spiclk");
|
|
if (IS_ERR(rs->spiclk)) {
|
|
dev_err(&pdev->dev, "Failed to get spi_pclk\n");
|
|
ret = PTR_ERR(rs->spiclk);
|
|
goto err_put_ctlr;
|
|
}
|
|
|
|
ret = clk_prepare_enable(rs->apb_pclk);
|
|
if (ret < 0) {
|
|
dev_err(&pdev->dev, "Failed to enable apb_pclk\n");
|
|
goto err_put_ctlr;
|
|
}
|
|
|
|
ret = clk_prepare_enable(rs->spiclk);
|
|
if (ret < 0) {
|
|
dev_err(&pdev->dev, "Failed to enable spi_clk\n");
|
|
goto err_disable_apbclk;
|
|
}
|
|
|
|
spi_enable_chip(rs, false);
|
|
|
|
ret = platform_get_irq(pdev, 0);
|
|
if (ret < 0)
|
|
goto err_disable_spiclk;
|
|
|
|
ret = devm_request_threaded_irq(&pdev->dev, ret, rockchip_spi_isr, NULL,
|
|
IRQF_ONESHOT, dev_name(&pdev->dev), ctlr);
|
|
if (ret)
|
|
goto err_disable_spiclk;
|
|
|
|
rs->dev = &pdev->dev;
|
|
rs->freq = clk_get_rate(rs->spiclk);
|
|
|
|
if (!of_property_read_u32(pdev->dev.of_node, "rx-sample-delay-ns",
|
|
&rsd_nsecs)) {
|
|
/* rx sample delay is expressed in parent clock cycles (max 3) */
|
|
u32 rsd = DIV_ROUND_CLOSEST(rsd_nsecs * (rs->freq >> 8),
|
|
1000000000 >> 8);
|
|
if (!rsd) {
|
|
dev_warn(rs->dev, "%u Hz are too slow to express %u ns delay\n",
|
|
rs->freq, rsd_nsecs);
|
|
} else if (rsd > CR0_RSD_MAX) {
|
|
rsd = CR0_RSD_MAX;
|
|
dev_warn(rs->dev, "%u Hz are too fast to express %u ns delay, clamping at %u ns\n",
|
|
rs->freq, rsd_nsecs,
|
|
CR0_RSD_MAX * 1000000000U / rs->freq);
|
|
}
|
|
rs->rsd = rsd;
|
|
}
|
|
|
|
rs->fifo_len = get_fifo_len(rs);
|
|
if (!rs->fifo_len) {
|
|
dev_err(&pdev->dev, "Failed to get fifo length\n");
|
|
ret = -EINVAL;
|
|
goto err_disable_spiclk;
|
|
}
|
|
|
|
pm_runtime_set_autosuspend_delay(&pdev->dev, ROCKCHIP_AUTOSUSPEND_TIMEOUT);
|
|
pm_runtime_use_autosuspend(&pdev->dev);
|
|
pm_runtime_set_active(&pdev->dev);
|
|
pm_runtime_enable(&pdev->dev);
|
|
|
|
ctlr->auto_runtime_pm = true;
|
|
ctlr->bus_num = pdev->id;
|
|
ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP | SPI_LSB_FIRST;
|
|
if (slave_mode) {
|
|
ctlr->mode_bits |= SPI_NO_CS;
|
|
ctlr->slave_abort = rockchip_spi_slave_abort;
|
|
} else {
|
|
ctlr->flags = SPI_MASTER_GPIO_SS;
|
|
ctlr->max_native_cs = ROCKCHIP_SPI_MAX_CS_NUM;
|
|
/*
|
|
* rk spi0 has two native cs, spi1..5 one cs only
|
|
* if num-cs is missing in the dts, default to 1
|
|
*/
|
|
if (of_property_read_u16(np, "num-cs", &ctlr->num_chipselect))
|
|
ctlr->num_chipselect = 1;
|
|
ctlr->use_gpio_descriptors = true;
|
|
}
|
|
ctlr->dev.of_node = pdev->dev.of_node;
|
|
ctlr->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8) | SPI_BPW_MASK(4);
|
|
ctlr->min_speed_hz = rs->freq / BAUDR_SCKDV_MAX;
|
|
ctlr->max_speed_hz = min(rs->freq / BAUDR_SCKDV_MIN, MAX_SCLK_OUT);
|
|
|
|
ctlr->set_cs = rockchip_spi_set_cs;
|
|
ctlr->transfer_one = rockchip_spi_transfer_one;
|
|
ctlr->max_transfer_size = rockchip_spi_max_transfer_size;
|
|
ctlr->handle_err = rockchip_spi_handle_err;
|
|
|
|
ctlr->dma_tx = dma_request_chan(rs->dev, "tx");
|
|
if (IS_ERR(ctlr->dma_tx)) {
|
|
/* Check tx to see if we need defer probing driver */
|
|
if (PTR_ERR(ctlr->dma_tx) == -EPROBE_DEFER) {
|
|
ret = -EPROBE_DEFER;
|
|
goto err_disable_pm_runtime;
|
|
}
|
|
dev_warn(rs->dev, "Failed to request TX DMA channel\n");
|
|
ctlr->dma_tx = NULL;
|
|
}
|
|
|
|
ctlr->dma_rx = dma_request_chan(rs->dev, "rx");
|
|
if (IS_ERR(ctlr->dma_rx)) {
|
|
if (PTR_ERR(ctlr->dma_rx) == -EPROBE_DEFER) {
|
|
ret = -EPROBE_DEFER;
|
|
goto err_free_dma_tx;
|
|
}
|
|
dev_warn(rs->dev, "Failed to request RX DMA channel\n");
|
|
ctlr->dma_rx = NULL;
|
|
}
|
|
|
|
if (ctlr->dma_tx && ctlr->dma_rx) {
|
|
rs->dma_addr_tx = mem->start + ROCKCHIP_SPI_TXDR;
|
|
rs->dma_addr_rx = mem->start + ROCKCHIP_SPI_RXDR;
|
|
ctlr->can_dma = rockchip_spi_can_dma;
|
|
}
|
|
|
|
ret = devm_spi_register_controller(&pdev->dev, ctlr);
|
|
if (ret < 0) {
|
|
dev_err(&pdev->dev, "Failed to register controller\n");
|
|
goto err_free_dma_rx;
|
|
}
|
|
|
|
return 0;
|
|
|
|
err_free_dma_rx:
|
|
if (ctlr->dma_rx)
|
|
dma_release_channel(ctlr->dma_rx);
|
|
err_free_dma_tx:
|
|
if (ctlr->dma_tx)
|
|
dma_release_channel(ctlr->dma_tx);
|
|
err_disable_pm_runtime:
|
|
pm_runtime_disable(&pdev->dev);
|
|
err_disable_spiclk:
|
|
clk_disable_unprepare(rs->spiclk);
|
|
err_disable_apbclk:
|
|
clk_disable_unprepare(rs->apb_pclk);
|
|
err_put_ctlr:
|
|
spi_controller_put(ctlr);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int rockchip_spi_remove(struct platform_device *pdev)
|
|
{
|
|
struct spi_controller *ctlr = spi_controller_get(platform_get_drvdata(pdev));
|
|
struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
|
|
|
|
pm_runtime_get_sync(&pdev->dev);
|
|
|
|
clk_disable_unprepare(rs->spiclk);
|
|
clk_disable_unprepare(rs->apb_pclk);
|
|
|
|
pm_runtime_put_noidle(&pdev->dev);
|
|
pm_runtime_disable(&pdev->dev);
|
|
pm_runtime_set_suspended(&pdev->dev);
|
|
|
|
if (ctlr->dma_tx)
|
|
dma_release_channel(ctlr->dma_tx);
|
|
if (ctlr->dma_rx)
|
|
dma_release_channel(ctlr->dma_rx);
|
|
|
|
spi_controller_put(ctlr);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
static int rockchip_spi_suspend(struct device *dev)
|
|
{
|
|
int ret;
|
|
struct spi_controller *ctlr = dev_get_drvdata(dev);
|
|
|
|
ret = spi_controller_suspend(ctlr);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = pm_runtime_force_suspend(dev);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
pinctrl_pm_select_sleep_state(dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int rockchip_spi_resume(struct device *dev)
|
|
{
|
|
int ret;
|
|
struct spi_controller *ctlr = dev_get_drvdata(dev);
|
|
struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
|
|
|
|
pinctrl_pm_select_default_state(dev);
|
|
|
|
ret = pm_runtime_force_resume(dev);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = spi_controller_resume(ctlr);
|
|
if (ret < 0) {
|
|
clk_disable_unprepare(rs->spiclk);
|
|
clk_disable_unprepare(rs->apb_pclk);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_PM_SLEEP */
|
|
|
|
#ifdef CONFIG_PM
|
|
static int rockchip_spi_runtime_suspend(struct device *dev)
|
|
{
|
|
struct spi_controller *ctlr = dev_get_drvdata(dev);
|
|
struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
|
|
|
|
clk_disable_unprepare(rs->spiclk);
|
|
clk_disable_unprepare(rs->apb_pclk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int rockchip_spi_runtime_resume(struct device *dev)
|
|
{
|
|
int ret;
|
|
struct spi_controller *ctlr = dev_get_drvdata(dev);
|
|
struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
|
|
|
|
ret = clk_prepare_enable(rs->apb_pclk);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = clk_prepare_enable(rs->spiclk);
|
|
if (ret < 0)
|
|
clk_disable_unprepare(rs->apb_pclk);
|
|
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_PM */
|
|
|
|
static const struct dev_pm_ops rockchip_spi_pm = {
|
|
SET_SYSTEM_SLEEP_PM_OPS(rockchip_spi_suspend, rockchip_spi_resume)
|
|
SET_RUNTIME_PM_OPS(rockchip_spi_runtime_suspend,
|
|
rockchip_spi_runtime_resume, NULL)
|
|
};
|
|
|
|
static const struct of_device_id rockchip_spi_dt_match[] = {
|
|
{ .compatible = "rockchip,px30-spi", },
|
|
{ .compatible = "rockchip,rk3036-spi", },
|
|
{ .compatible = "rockchip,rk3066-spi", },
|
|
{ .compatible = "rockchip,rk3188-spi", },
|
|
{ .compatible = "rockchip,rk3228-spi", },
|
|
{ .compatible = "rockchip,rk3288-spi", },
|
|
{ .compatible = "rockchip,rk3308-spi", },
|
|
{ .compatible = "rockchip,rk3328-spi", },
|
|
{ .compatible = "rockchip,rk3368-spi", },
|
|
{ .compatible = "rockchip,rk3399-spi", },
|
|
{ .compatible = "rockchip,rv1108-spi", },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(of, rockchip_spi_dt_match);
|
|
|
|
static struct platform_driver rockchip_spi_driver = {
|
|
.driver = {
|
|
.name = DRIVER_NAME,
|
|
.pm = &rockchip_spi_pm,
|
|
.of_match_table = of_match_ptr(rockchip_spi_dt_match),
|
|
},
|
|
.probe = rockchip_spi_probe,
|
|
.remove = rockchip_spi_remove,
|
|
};
|
|
|
|
module_platform_driver(rockchip_spi_driver);
|
|
|
|
MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>");
|
|
MODULE_DESCRIPTION("ROCKCHIP SPI Controller Driver");
|
|
MODULE_LICENSE("GPL v2");
|