881 lines
22 KiB
C
881 lines
22 KiB
C
/*
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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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* This program is free software; you can redistribute it and/or modify it
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* under the terms and conditions of the GNU General Public License,
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* version 2, as published by the Free Software Foundation.
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*
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* This program is distributed in the hope it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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* more details.
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*
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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/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_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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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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};
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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 fifo;
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for (fifo = 2; fifo < 32; fifo++) {
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writel_relaxed(fifo, rs->regs + ROCKCHIP_SPI_TXFTLR);
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if (fifo != readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFTLR))
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break;
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}
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writel_relaxed(0, rs->regs + ROCKCHIP_SPI_TXFTLR);
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return (fifo == 31) ? 0 : fifo;
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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_master *master = spi->master;
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struct rockchip_spi *rs = spi_master_get_devdata(master);
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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_master *master,
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struct spi_message *msg)
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{
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struct rockchip_spi *rs = spi_master_get_devdata(master);
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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(master->dma_tx);
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if (atomic_read(&rs->state) & RXDMA)
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dmaengine_terminate_async(master->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;
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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_master *master = dev_id;
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struct rockchip_spi *rs = spi_master_get_devdata(master);
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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(master);
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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_master *master = data;
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struct rockchip_spi *rs = spi_master_get_devdata(master);
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int state = atomic_fetch_andnot(RXDMA, &rs->state);
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if (state & TXDMA)
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return;
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spi_enable_chip(rs, false);
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spi_finalize_current_transfer(master);
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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_master *master = data;
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struct rockchip_spi *rs = spi_master_get_devdata(master);
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int state = atomic_fetch_andnot(TXDMA, &rs->state);
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if (state & RXDMA)
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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(master);
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}
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static int rockchip_spi_prepare_dma(struct rockchip_spi *rs,
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struct spi_master *master, 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 = 1,
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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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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 = master;
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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 / 2,
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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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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(master->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 = master;
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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(master->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(master->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)
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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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cr0 |= rs->rsd << CR0_RSD_OFFSET;
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cr0 |= (spi->mode & 0x3U) << CR0_SCPH_OFFSET;
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if (spi->mode & SPI_LSB_FIRST)
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cr0 |= CR0_FBM_LSB << CR0_FBM_OFFSET;
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if (xfer->rx_buf && xfer->tx_buf)
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cr0 |= CR0_XFM_TR << CR0_XFM_OFFSET;
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else if (xfer->rx_buf)
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cr0 |= CR0_XFM_RO << CR0_XFM_OFFSET;
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else if (use_dma)
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cr0 |= CR0_XFM_TO << CR0_XFM_OFFSET;
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switch (xfer->bits_per_word) {
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case 4:
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cr0 |= CR0_DFS_4BIT << CR0_DFS_OFFSET;
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cr1 = xfer->len - 1;
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break;
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case 8:
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cr0 |= CR0_DFS_8BIT << CR0_DFS_OFFSET;
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cr1 = xfer->len - 1;
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break;
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case 16:
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|
cr0 |= CR0_DFS_16BIT << CR0_DFS_OFFSET;
|
|
cr1 = xfer->len / 2 - 1;
|
|
break;
|
|
default:
|
|
/* we only whitelist 4, 8 and 16 bit words in
|
|
* master->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 - 1, rs->regs + ROCKCHIP_SPI_DMATDLR);
|
|
writel_relaxed(0, 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_transfer_one(
|
|
struct spi_master *master,
|
|
struct spi_device *spi,
|
|
struct spi_transfer *xfer)
|
|
{
|
|
struct rockchip_spi *rs = spi_master_get_devdata(master);
|
|
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 = master->can_dma ? master->can_dma(master, spi, xfer) : false;
|
|
|
|
rockchip_spi_config(rs, spi, xfer, use_dma);
|
|
|
|
if (use_dma)
|
|
return rockchip_spi_prepare_dma(rs, master, xfer);
|
|
|
|
return rockchip_spi_prepare_irq(rs, xfer);
|
|
}
|
|
|
|
static bool rockchip_spi_can_dma(struct spi_master *master,
|
|
struct spi_device *spi,
|
|
struct spi_transfer *xfer)
|
|
{
|
|
struct rockchip_spi *rs = spi_master_get_devdata(master);
|
|
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_master *master;
|
|
struct resource *mem;
|
|
u32 rsd_nsecs;
|
|
|
|
master = spi_alloc_master(&pdev->dev, sizeof(struct rockchip_spi));
|
|
if (!master)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, master);
|
|
|
|
rs = spi_master_get_devdata(master);
|
|
|
|
/* 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_master;
|
|
}
|
|
|
|
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_master;
|
|
}
|
|
|
|
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_master;
|
|
}
|
|
|
|
ret = clk_prepare_enable(rs->apb_pclk);
|
|
if (ret < 0) {
|
|
dev_err(&pdev->dev, "Failed to enable apb_pclk\n");
|
|
goto err_put_master;
|
|
}
|
|
|
|
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), master);
|
|
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_active(&pdev->dev);
|
|
pm_runtime_enable(&pdev->dev);
|
|
|
|
master->auto_runtime_pm = true;
|
|
master->bus_num = pdev->id;
|
|
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP | SPI_LSB_FIRST;
|
|
master->num_chipselect = ROCKCHIP_SPI_MAX_CS_NUM;
|
|
master->dev.of_node = pdev->dev.of_node;
|
|
master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8) | SPI_BPW_MASK(4);
|
|
master->min_speed_hz = rs->freq / BAUDR_SCKDV_MAX;
|
|
master->max_speed_hz = min(rs->freq / BAUDR_SCKDV_MIN, MAX_SCLK_OUT);
|
|
|
|
master->set_cs = rockchip_spi_set_cs;
|
|
master->transfer_one = rockchip_spi_transfer_one;
|
|
master->max_transfer_size = rockchip_spi_max_transfer_size;
|
|
master->handle_err = rockchip_spi_handle_err;
|
|
master->flags = SPI_MASTER_GPIO_SS;
|
|
|
|
master->dma_tx = dma_request_chan(rs->dev, "tx");
|
|
if (IS_ERR(master->dma_tx)) {
|
|
/* Check tx to see if we need defer probing driver */
|
|
if (PTR_ERR(master->dma_tx) == -EPROBE_DEFER) {
|
|
ret = -EPROBE_DEFER;
|
|
goto err_disable_pm_runtime;
|
|
}
|
|
dev_warn(rs->dev, "Failed to request TX DMA channel\n");
|
|
master->dma_tx = NULL;
|
|
}
|
|
|
|
master->dma_rx = dma_request_chan(rs->dev, "rx");
|
|
if (IS_ERR(master->dma_rx)) {
|
|
if (PTR_ERR(master->dma_rx) == -EPROBE_DEFER) {
|
|
ret = -EPROBE_DEFER;
|
|
goto err_free_dma_tx;
|
|
}
|
|
dev_warn(rs->dev, "Failed to request RX DMA channel\n");
|
|
master->dma_rx = NULL;
|
|
}
|
|
|
|
if (master->dma_tx && master->dma_rx) {
|
|
rs->dma_addr_tx = mem->start + ROCKCHIP_SPI_TXDR;
|
|
rs->dma_addr_rx = mem->start + ROCKCHIP_SPI_RXDR;
|
|
master->can_dma = rockchip_spi_can_dma;
|
|
}
|
|
|
|
ret = devm_spi_register_master(&pdev->dev, master);
|
|
if (ret < 0) {
|
|
dev_err(&pdev->dev, "Failed to register master\n");
|
|
goto err_free_dma_rx;
|
|
}
|
|
|
|
return 0;
|
|
|
|
err_free_dma_rx:
|
|
if (master->dma_rx)
|
|
dma_release_channel(master->dma_rx);
|
|
err_free_dma_tx:
|
|
if (master->dma_tx)
|
|
dma_release_channel(master->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_master:
|
|
spi_master_put(master);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int rockchip_spi_remove(struct platform_device *pdev)
|
|
{
|
|
struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
|
|
struct rockchip_spi *rs = spi_master_get_devdata(master);
|
|
|
|
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 (master->dma_tx)
|
|
dma_release_channel(master->dma_tx);
|
|
if (master->dma_rx)
|
|
dma_release_channel(master->dma_rx);
|
|
|
|
spi_master_put(master);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
static int rockchip_spi_suspend(struct device *dev)
|
|
{
|
|
int ret;
|
|
struct spi_master *master = dev_get_drvdata(dev);
|
|
|
|
ret = spi_master_suspend(master);
|
|
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_master *master = dev_get_drvdata(dev);
|
|
struct rockchip_spi *rs = spi_master_get_devdata(master);
|
|
|
|
pinctrl_pm_select_default_state(dev);
|
|
|
|
ret = pm_runtime_force_resume(dev);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = spi_master_resume(master);
|
|
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_master *master = dev_get_drvdata(dev);
|
|
struct rockchip_spi *rs = spi_master_get_devdata(master);
|
|
|
|
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_master *master = dev_get_drvdata(dev);
|
|
struct rockchip_spi *rs = spi_master_get_devdata(master);
|
|
|
|
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,rv1108-spi", },
|
|
{ .compatible = "rockchip,rk3036-spi", },
|
|
{ .compatible = "rockchip,rk3066-spi", },
|
|
{ .compatible = "rockchip,rk3188-spi", },
|
|
{ .compatible = "rockchip,rk3228-spi", },
|
|
{ .compatible = "rockchip,rk3288-spi", },
|
|
{ .compatible = "rockchip,rk3368-spi", },
|
|
{ .compatible = "rockchip,rk3399-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");
|