[2/2] spi: sprd: Add SPI driver for Spreadtrum SC9860

Message ID	99befd2badc4dffb59662fca1e11d79f18b64755.1533638405.git.baolin.wang@linaro.org (mailing list archive)
State	New, archived
Headers	show Return-Path: <linux-spi-owner@kernel.org> From: Baolin Wang <baolin.wang@linaro.org> To: broonie@kernel.org, robh+dt@kernel.org, mark.rutland@arm.com Cc: orsonzhai@gmail.com, zhang.lyra@gmail.com, lanqing.liu@spreadtrum.com, baolin.wang@linaro.org, linux-spi@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/2] spi: sprd: Add SPI driver for Spreadtrum SC9860 Date: Tue, 7 Aug 2018 18:43:38 +0800 Message-Id: <99befd2badc4dffb59662fca1e11d79f18b64755.1533638405.git.baolin.wang@linaro.org> In-Reply-To: <64681bf903104c8a02f118294e616e2a12a5ebe4.1533638405.git.baolin.wang@linaro.org> References: <64681bf903104c8a02f118294e616e2a12a5ebe4.1533638405.git.baolin.wang@linaro.org> In-Reply-To: <64681bf903104c8a02f118294e616e2a12a5ebe4.1533638405.git.baolin.wang@linaro.org> References: <64681bf903104c8a02f118294e616e2a12a5ebe4.1533638405.git.baolin.wang@linaro.org> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk
Series	[1/2] dt-bindings: spi: Add Spreadtrum SPI controller documentation \| expand [1/2] dt-bindings: spi: Add Spreadtrum SPI controller documentation [2/2] spi: sprd: Add SPI driver for Spreadtrum SC9860

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index ad5d68e..c49c40c 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -596,6 +596,12 @@ config SPI_SIRF help SPI driver for CSR SiRFprimaII SoCs +config SPI_SPRD + tristate "Spreadtrum SPI controller" + depends on ARCH_SPRD || COMPILE_TEST + help + SPI driver for Spreadtrum SoCs. + config SPI_SPRD_ADI tristate "Spreadtrum ADI controller" depends on ARCH_SPRD || COMPILE_TEST diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index cb1f437..5bb6b37 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -88,6 +88,7 @@ obj-$(CONFIG_SPI_SH_HSPI) += spi-sh-hspi.o obj-$(CONFIG_SPI_SH_MSIOF) += spi-sh-msiof.o obj-$(CONFIG_SPI_SH_SCI) += spi-sh-sci.o obj-$(CONFIG_SPI_SIRF) += spi-sirf.o +obj-$(CONFIG_SPI_SPRD) += spi-sprd.o obj-$(CONFIG_SPI_SPRD_ADI) += spi-sprd-adi.o obj-$(CONFIG_SPI_STM32) += spi-stm32.o obj-$(CONFIG_SPI_ST_SSC4) += spi-st-ssc4.o diff --git a/drivers/spi/spi-sprd.c b/drivers/spi/spi-sprd.c new file mode 100644 index 0000000..cd77a5a --- /dev/null +++ b/drivers/spi/spi-sprd.c @@ -0,0 +1,771 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Spreadtrum Communications Inc. + +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/spi/spi.h> + +#define SPRD_SPI_TXD 0x0 +#define SPRD_SPI_CLKD 0x4 +#define SPRD_SPI_CTL0 0x8 +#define SPRD_SPI_CTL1 0xc +#define SPRD_SPI_CTL2 0x10 +#define SPRD_SPI_CTL3 0x14 +#define SPRD_SPI_CTL4 0x18 +#define SPRD_SPI_CTL5 0x1c +#define SPRD_SPI_INT_EN 0x20 +#define SPRD_SPI_INT_CLR 0x24 +#define SPRD_SPI_INT_RAW_STS 0x28 +#define SPRD_SPI_INT_MASK_STS 0x2c +#define SPRD_SPI_STS1 0x30 +#define SPRD_SPI_STS2 0x34 +#define SPRD_SPI_DSP_WAIT 0x38 +#define SPRD_SPI_STS3 0x3c +#define SPRD_SPI_CTL6 0x40 +#define SPRD_SPI_STS4 0x44 +#define SPRD_SPI_FIFO_RST 0x48 +#define SPRD_SPI_CTL7 0x4c +#define SPRD_SPI_STS5 0x50 +#define SPRD_SPI_CTL8 0x54 +#define SPRD_SPI_CTL9 0x58 +#define SPRD_SPI_CTL10 0x5c +#define SPRD_SPI_CTL11 0x60 +#define SPRD_SPI_CTL12 0x64 +#define SPRD_SPI_STS6 0x68 +#define SPRD_SPI_STS7 0x6c +#define SPRD_SPI_STS8 0x70 +#define SPRD_SPI_STS9 0x74 + +/* Bits & mask definition for register CTL0 */ +#define SPRD_SPI_SCK_REV BIT(13) +#define SPRD_SPI_NG_TX BIT(1) +#define SPRD_SPI_NG_RX BIT(0) +#define SPRD_SPI_CHNL_LEN_MASK GENMASK(4, 0) +#define SPRD_SPI_CSN_MASK GENMASK(11, 8) +#define SPRD_SPI_CS0_VALID BIT(8) + +/* Bits & mask definition for register SPI_INT_EN */ +#define SPRD_SPI_TX_END_INT_EN BIT(8) +#define SPRD_SPI_RX_END_INT_EN BIT(9) + +/* Bits & mask definition for register SPI_INT_RAW_STS */ +#define SPRD_SPI_TX_END_RAW BIT(8) +#define SPRD_SPI_RX_END_RAW BIT(9) + +/* Bits & mask definition for register SPI_INT_CLR */ +#define SPRD_SPI_TX_END_CLR BIT(8) +#define SPRD_SPI_RX_END_CLR BIT(9) + +/* Bits & mask definition for register INT_MASK_STS */ +#define SPRD_SPI_MASK_RX_END BIT(9) +#define SPRD_SPI_MASK_TX_END BIT(8) + +/* Bits & mask definition for register STS2 */ +#define SPRD_SPI_TX_BUSY BIT(8) + +/* Bits & mask definition for register CTL1 */ +#define SPRD_SPI_RX_MODE BIT(12) +#define SPRD_SPI_TX_MODE BIT(13) +#define SPRD_SPI_RTX_MD_MASK GENMASK(13, 12) + +/* Bits & mask definition for register CTL2 */ +#define SPRD_SPI_DMA_EN BIT(6) + +/* Bits & mask definition for register CTL4 */ +#define SPRD_SPI_START_RX BIT(9) +#define SPRD_SPI_ONLY_RECV_MASK GENMASK(8, 0) + +/* Bits & mask definition for register SPI_INT_CLR */ +#define SPRD_SPI_RX_END_INT_CLR BIT(9) +#define SPRD_SPI_TX_END_INT_CLR BIT(8) + +/* Bits & mask definition for register SPI_INT_RAW */ +#define SPRD_SPI_RX_END_IRQ BIT(9) +#define SPRD_SPI_TX_END_IRQ BIT(8) + +/* Bits & mask definition for register CTL12 */ +#define SPRD_SPI_SW_RX_REQ BIT(0) +#define SPRD_SPI_SW_TX_REQ BIT(1) + +/* Bits & mask definition for register CTL7 */ +#define SPRD_SPI_DATA_LINE2_EN BIT(15) +#define SPRD_SPI_MODE_MASK GENMASK(5, 3) +#define SPRD_SPI_MODE_OFFSET 3 +#define SPRD_SPI_3WIRE_MODE 4 +#define SPRD_SPI_4WIRE_MODE 0 + +/* Bits & mask definition for register CTL8 */ +#define SPRD_SPI_TX_MAX_LEN_MASK GENMASK(19, 0) +#define SPRD_SPI_TX_LEN_H_MASK GENMASK(3, 0) +#define SPRD_SPI_TX_LEN_H_OFFSET 16 + +/* Bits & mask definition for register CTL9 */ +#define SPRD_SPI_TX_LEN_L_MASK GENMASK(15, 0) + +/* Bits & mask definition for register CTL10 */ +#define SPRD_SPI_RX_MAX_LEN_MASK GENMASK(19, 0) +#define SPRD_SPI_RX_LEN_H_MASK GENMASK(3, 0) +#define SPRD_SPI_RX_LEN_H_OFFSET 16 + +/* Bits & mask definition for register CTL11 */ +#define SPRD_SPI_RX_LEN_L_MASK GENMASK(15, 0) + +/* Default interval value */ +#define SPRD_SPI_ITVL_NUM 0x9 + +#define SPRD_SPI_FIFO_SIZE 32 +#define SPRD_SPI_CHIP_CS_NUM 0x4 +#define SPRD_SPI_CHNL_LEN 2 +#define SPRD_SPI_DEFAULT_SOURCE 26000000 +#define SPRD_SPI_MAX_SPEED_HZ 48000000 +#define SPRD_SPI_HZ 1000000 +#define SPRD_SPI_AUTOSUSPEND_DELAY 100 + +struct sprd_spi { + void __iomem *base; + struct device *dev; + struct clk *clk; + u32 src_clk; + u32 hw_mode; + u32 trans_len; + u32 trans_mode; + u32 interval; + u32 len; + int status; + const void *tx_buf; + void *rx_buf; + int (*read_bufs)(struct sprd_spi *ss, u32 len); + int (*write_bufs)(struct sprd_spi *ss, u32 len); +}; + +static u32 sprd_spi_transfer_max_timeout(struct sprd_spi *ss, + struct spi_transfer *t) +{ + /* + * The time spent on transmission of the full FIFO data is the maximum + * SPI transmission time. + */ + u32 size = t->bits_per_word * SPRD_SPI_FIFO_SIZE; + u32 bit_time_us = SPRD_SPI_HZ / t->speed_hz + 1; + u32 total_time_us = size * bit_time_us; + /* + * There is an interval between data and the data in our SPI hardware, + * so the total transmission time need add the interval time. + * + * The inteval calculation formula: + * interval time (source clock cycles) = interval * 4 + 10. + */ + u32 interval_cycle = SPRD_SPI_FIFO_SIZE * ((ss->interval << 2) + 10); + u32 interval_time_us = interval_cycle * SPRD_SPI_HZ / ss->src_clk + 1; + + return total_time_us + interval_time_us; +} + +static int sprd_spi_wait_for_tx_end(struct sprd_spi *ss, struct spi_transfer *t) +{ + u32 val, us; + int ret; + + us = sprd_spi_transfer_max_timeout(ss, t); + ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_INT_RAW_STS, val, + val & SPRD_SPI_TX_END_IRQ, 0, us); + if (ret) { + dev_err(ss->dev, "SPI error, spi send timeout!\n"); + return ret; + } + + ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_STS2, val, + !(val & SPRD_SPI_TX_BUSY), 0, us); + if (ret) { + dev_err(ss->dev, "SPI error, spi busy timeout!\n"); + return ret; + } + + writel_relaxed(SPRD_SPI_TX_END_INT_CLR, ss->base + SPRD_SPI_INT_CLR); + + return 0; +} + +static int sprd_spi_wait_for_rx_end(struct sprd_spi *ss, struct spi_transfer *t) +{ + u32 val, us; + int ret; + + us = sprd_spi_transfer_max_timeout(ss, t); + ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_INT_RAW_STS, val, + val & SPRD_SPI_RX_END_IRQ, 0, us); + if (ret) { + dev_err(ss->dev, "SPI error, spi rx timeout!\n"); + return ret; + } + + writel_relaxed(SPRD_SPI_RX_END_INT_CLR, ss->base + SPRD_SPI_INT_CLR); + + return 0; +} + +static void sprd_spi_tx_req(struct sprd_spi *ss) +{ + writel_relaxed(SPRD_SPI_SW_TX_REQ, ss->base + SPRD_SPI_CTL12); +} + +static void sprd_spi_rx_req(struct sprd_spi *ss) +{ + writel_relaxed(SPRD_SPI_SW_RX_REQ, ss->base + SPRD_SPI_CTL12); +} + +static void sprd_spi_enter_idle(struct sprd_spi *ss) +{ + u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL1); + + val &= ~SPRD_SPI_RTX_MD_MASK; + writel_relaxed(val, ss->base + SPRD_SPI_CTL1); +} + +static void sprd_spi_set_transfer_bits(struct sprd_spi *ss, u32 bits) +{ + u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL0); + + /* Set the valid bits for every transaction */ + val &= ~(SPRD_SPI_CHNL_LEN_MASK << SPRD_SPI_CHNL_LEN); + val |= bits << SPRD_SPI_CHNL_LEN; + writel_relaxed(val, ss->base + SPRD_SPI_CTL0); +} + +static void sprd_spi_set_tx_length(struct sprd_spi *ss, u32 length) +{ + u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL8); + + length &= SPRD_SPI_TX_MAX_LEN_MASK; + val &= ~SPRD_SPI_TX_LEN_H_MASK; + val |= length >> SPRD_SPI_TX_LEN_H_OFFSET; + writel_relaxed(val, ss->base + SPRD_SPI_CTL8); + + val = length & SPRD_SPI_TX_LEN_L_MASK; + writel_relaxed(val, ss->base + SPRD_SPI_CTL9); +} + +static void sprd_spi_set_rx_length(struct sprd_spi *ss, u32 length) +{ + u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL10); + + length &= SPRD_SPI_RX_MAX_LEN_MASK; + val &= ~SPRD_SPI_RX_LEN_H_MASK; + val |= length >> SPRD_SPI_RX_LEN_H_OFFSET; + writel_relaxed(val, ss->base + SPRD_SPI_CTL10); + + val = length & SPRD_SPI_RX_LEN_L_MASK; + writel_relaxed(val, ss->base + SPRD_SPI_CTL11); +} + +static void sprd_spi_chipselect(struct spi_device *sdev, bool cs) +{ + struct spi_controller *sctlr = sdev->controller; + struct sprd_spi *ss = spi_controller_get_devdata(sctlr); + u32 val; + int ret; + + ret = pm_runtime_get_sync(ss->dev); + if (ret < 0) { + dev_err(ss->dev, "failed to resume SPI controller\n"); + return; + } + + val = readl_relaxed(ss->base + SPRD_SPI_CTL0); + /* The SPI controller will pull down CS pin if cs is 0 */ + if (!cs) { + val &= ~SPRD_SPI_CS0_VALID; + writel_relaxed(val, ss->base + SPRD_SPI_CTL0); + } else { + val |= SPRD_SPI_CSN_MASK; + writel_relaxed(val, ss->base + SPRD_SPI_CTL0); + } + + pm_runtime_mark_last_busy(ss->dev); + pm_runtime_put_autosuspend(ss->dev); +} + +static int sprd_spi_write_only_receive(struct sprd_spi *ss, u32 len) +{ + u32 val; + + /* Clear the start receive bit and reset receive data number */ + val = readl_relaxed(ss->base + SPRD_SPI_CTL4); + val &= ~(SPRD_SPI_START_RX | SPRD_SPI_ONLY_RECV_MASK); + writel_relaxed(val, ss->base + SPRD_SPI_CTL4); + + /* Set the receive data length */ + val = readl_relaxed(ss->base + SPRD_SPI_CTL4); + val |= len & SPRD_SPI_ONLY_RECV_MASK; + writel_relaxed(val, ss->base + SPRD_SPI_CTL4); + + /* Trigger to receive data */ + val = readl_relaxed(ss->base + SPRD_SPI_CTL4); + val |= SPRD_SPI_START_RX; + writel_relaxed(val, ss->base + SPRD_SPI_CTL4); + + return len; +} + +static int sprd_spi_write_bufs_u8(struct sprd_spi *ss, u32 len) +{ + u8 *tx_p = (u8 *)ss->tx_buf; + int i; + + for (i = 0; i < len; i++) + writeb_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD); + + ss->tx_buf += i; + return i; +} + +static int sprd_spi_write_bufs_u16(struct sprd_spi *ss, u32 len) +{ + u16 *tx_p = (u16 *)ss->tx_buf; + int i; + + for (i = 0; i < len; i++) + writew_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD); + + ss->tx_buf += i << 1; + return i << 1; +} + +static int sprd_spi_write_bufs_u32(struct sprd_spi *ss, u32 len) +{ + u32 *tx_p = (u32 *)ss->tx_buf; + int i; + + for (i = 0; i < len; i++) + writel_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD); + + ss->tx_buf += i << 2; + return i << 2; +} + +static int sprd_spi_read_bufs_u8(struct sprd_spi *ss, u32 len) +{ + u8 *rx_p = (u8 *)ss->rx_buf; + int i; + + for (i = 0; i < len; i++) + rx_p[i] = readb_relaxed(ss->base + SPRD_SPI_TXD); + + ss->rx_buf += i; + return i; +} + +static int sprd_spi_read_bufs_u16(struct sprd_spi *ss, u32 len) +{ + u16 *rx_p = (u16 *)ss->rx_buf; + int i; + + for (i = 0; i < len; i++) + rx_p[i] = readw_relaxed(ss->base + SPRD_SPI_TXD); + + ss->rx_buf += i << 1; + return i << 1; +} + +static int sprd_spi_read_bufs_u32(struct sprd_spi *ss, u32 len) +{ + u32 *rx_p = (u32 *)ss->rx_buf; + int i; + + for (i = 0; i < len; i++) + rx_p[i] = readl_relaxed(ss->base + SPRD_SPI_TXD); + + ss->rx_buf += i << 2; + return i << 2; +} + +static int sprd_spi_txrx_bufs(struct spi_device *sdev, struct spi_transfer *t) +{ + struct sprd_spi *ss = spi_controller_get_devdata(sdev->controller); + u32 trans_len = ss->trans_len, len; + int ret, write_size = 0; + + while (trans_len) { + len = trans_len > SPRD_SPI_FIFO_SIZE ? SPRD_SPI_FIFO_SIZE : + trans_len; + if (ss->trans_mode & SPRD_SPI_TX_MODE) { + sprd_spi_set_tx_length(ss, len); + write_size += ss->write_bufs(ss, len); + + /* + * For our 3 wires mode or dual TX line mode, we need + * to request the controller to transfer. + */ + if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL) + sprd_spi_tx_req(ss); + + ret = sprd_spi_wait_for_tx_end(ss, t); + } else { + sprd_spi_set_rx_length(ss, len); + + /* + * For our 3 wires mode or dual TX line mode, we need + * to request the controller to read. + */ + if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL) + sprd_spi_rx_req(ss); + else + write_size += ss->write_bufs(ss, len); + + ret = sprd_spi_wait_for_rx_end(ss, t); + } + + if (ret) + goto complete; + + if (ss->trans_mode & SPRD_SPI_RX_MODE) + ss->read_bufs(ss, len); + + trans_len -= len; + } + + ret = write_size; + +complete: + sprd_spi_enter_idle(ss); + + return ret; +} + +static void sprd_spi_set_speed(struct sprd_spi *ss, u32 speed_hz) +{ + /* + * From SPI datasheet, the prescale calculation formula: + * prescale = SPI source clock / (2 * SPI_freq) - 1; + */ + u32 clk_div = ss->src_clk / (speed_hz << 1) - 1; + + writel_relaxed(clk_div, ss->base + SPRD_SPI_CLKD); +} + +static int sprd_spi_setup_transfer(struct spi_device *sdev, + struct spi_transfer *t) +{ + struct sprd_spi *ss = spi_controller_get_devdata(sdev->controller); + u8 bits_per_word = t->bits_per_word; + u32 val, mode = 0; + + ss->len = t->len; + ss->tx_buf = t->tx_buf; + ss->rx_buf = t->rx_buf; + + /* Set tansfer speed and valid bits */ + sprd_spi_set_speed(ss, t->speed_hz); + sprd_spi_set_transfer_bits(ss, bits_per_word); + + bits_per_word = bits_per_word > 16 ? round_up(bits_per_word, 16) : + round_up(bits_per_word, 8); + switch (bits_per_word) { + case 8: + ss->trans_len = t->len; + ss->read_bufs = sprd_spi_read_bufs_u8; + ss->write_bufs = sprd_spi_write_bufs_u8; + break; + case 16: + ss->trans_len = t->len >> 1; + ss->read_bufs = sprd_spi_read_bufs_u16; + ss->write_bufs = sprd_spi_write_bufs_u16; + break; + case 32: + ss->trans_len = t->len >> 2; + ss->read_bufs = sprd_spi_read_bufs_u32; + ss->write_bufs = sprd_spi_write_bufs_u32; + break; + } + + /* Set transfer read or write mode */ + val = readl_relaxed(ss->base + SPRD_SPI_CTL1); + val &= ~SPRD_SPI_RTX_MD_MASK; + if (t->tx_buf) + mode |= SPRD_SPI_TX_MODE; + if (t->rx_buf) + mode |= SPRD_SPI_RX_MODE; + + writel_relaxed(val | mode, ss->base + SPRD_SPI_CTL1); + + ss->trans_mode = mode; + + /* + * If in only receive mode, we need to trigger the SPI controller to + * receive data automatically. + */ + if (ss->trans_mode == SPRD_SPI_RX_MODE) + ss->write_bufs = sprd_spi_write_only_receive; + + return 0; +} + +static int sprd_spi_transfer_one(struct spi_controller *sctlr, + struct spi_device *sdev, + struct spi_transfer *t) +{ + struct sprd_spi *ss = spi_controller_get_devdata(sctlr); + int ret; + + ret = pm_runtime_get_sync(ss->dev); + if (ret < 0) { + dev_err(ss->dev, "failed to resume SPI controller\n"); + goto rpm_err; + } + + ret = sprd_spi_setup_transfer(sdev, t); + if (ret) + goto setup_err; + + ret = sprd_spi_txrx_bufs(sdev, t); + if (ret == t->len) + ret = 0; + else if (ret >= 0) + ret = -EREMOTEIO; + +setup_err: + pm_runtime_mark_last_busy(ss->dev); + pm_runtime_put_autosuspend(ss->dev); +rpm_err: + spi_finalize_current_transfer(sctlr); + + return ret; +} + +static void sprd_spi_init_hw(struct sprd_spi *ss) +{ + u32 val = SPRD_SPI_CSN_MASK; + + /* Set default chip selection, clock phase and clock polarity */ + val |= ss->hw_mode & SPI_CPHA ? SPRD_SPI_NG_RX : SPRD_SPI_NG_TX; + val |= ss->hw_mode & SPI_CPOL ? SPRD_SPI_SCK_REV : 0; + writel_relaxed(val, ss->base + SPRD_SPI_CTL0); + + /* Set the intervals of two SPI frames */ + writel_relaxed(ss->interval, ss->base + SPRD_SPI_CTL5); + + /* Reset SPI fifo */ + writel_relaxed(1, ss->base + SPRD_SPI_FIFO_RST); + writel_relaxed(0, ss->base + SPRD_SPI_FIFO_RST); + + /* Set SPI work mode */ + val = readl_relaxed(ss->base + SPRD_SPI_CTL7); + val &= ~SPRD_SPI_MODE_MASK; + + if (ss->hw_mode & SPI_3WIRE) + val |= SPRD_SPI_3WIRE_MODE << SPRD_SPI_MODE_OFFSET; + else + val |= SPRD_SPI_4WIRE_MODE << SPRD_SPI_MODE_OFFSET; + + if (ss->hw_mode & SPI_TX_DUAL) + val |= SPRD_SPI_DATA_LINE2_EN; + else + val &= ~SPRD_SPI_DATA_LINE2_EN; + + writel_relaxed(val, ss->base + SPRD_SPI_CTL7); +} + +static int sprd_spi_setup(struct spi_device *spi_dev) +{ + struct spi_controller *sctlr = spi_dev->controller; + struct sprd_spi *ss = spi_controller_get_devdata(sctlr); + int ret; + + ret = pm_runtime_get_sync(ss->dev); + if (ret < 0) { + dev_err(ss->dev, "failed to resume SPI controller\n"); + return ret; + } + + ss->hw_mode = spi_dev->mode; + sprd_spi_init_hw(ss); + + pm_runtime_mark_last_busy(ss->dev); + pm_runtime_put_autosuspend(ss->dev); + + return 0; +} + +static int sprd_spi_clk_init(struct platform_device *pdev, struct sprd_spi *ss) +{ + struct clk *clk_spi, *clk_parent; + + clk_spi = devm_clk_get(&pdev->dev, "spi"); + if (IS_ERR(clk_spi)) { + dev_warn(&pdev->dev, "can't get the spi clock\n"); + clk_spi = NULL; + } + + clk_parent = devm_clk_get(&pdev->dev, "source"); + if (IS_ERR(clk_parent)) { + dev_warn(&pdev->dev, "can't get the source clock\n"); + clk_parent = NULL; + } + + ss->clk = devm_clk_get(&pdev->dev, "enable"); + if (IS_ERR(ss->clk)) { + dev_err(&pdev->dev, "can't get the enable clock\n"); + return PTR_ERR(ss->clk); + } + + if (!clk_set_parent(clk_spi, clk_parent)) + ss->src_clk = clk_get_rate(clk_spi); + else + ss->src_clk = SPRD_SPI_DEFAULT_SOURCE; + + return 0; +} + +static int sprd_spi_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct spi_controller *sctlr; + struct resource *res; + struct sprd_spi *ss; + int ret; + + pdev->id = of_alias_get_id(pdev->dev.of_node, "spi"); + sctlr = spi_alloc_master(&pdev->dev, sizeof(*ss)); + if (!sctlr) + return -ENOMEM; + + ss = spi_controller_get_devdata(sctlr); + if (of_property_read_u32(np, "sprd,spi-interval", &ss->interval)) + ss->interval = SPRD_SPI_ITVL_NUM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + ss->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(ss->base)) { + ret = PTR_ERR(ss->base); + goto free_controller; + } + + ss->dev = &pdev->dev; + sctlr->dev.of_node = pdev->dev.of_node; + sctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE | SPI_TX_DUAL; + sctlr->bus_num = pdev->id; + sctlr->setup = sprd_spi_setup; + sctlr->set_cs = sprd_spi_chipselect; + sctlr->transfer_one = sprd_spi_transfer_one; + sctlr->max_speed_hz = (ss->src_clk / 2) < SPRD_SPI_MAX_SPEED_HZ ? + ss->src_clk / 2 : SPRD_SPI_MAX_SPEED_HZ; + + platform_set_drvdata(pdev, sctlr); + ret = sprd_spi_clk_init(pdev, ss); + if (ret) + goto free_controller; + + ret = clk_prepare_enable(ss->clk); + if (ret) + goto free_controller; + + ret = pm_runtime_set_active(&pdev->dev); + if (ret < 0) + goto disable_clk; + + pm_runtime_set_autosuspend_delay(&pdev->dev, + SPRD_SPI_AUTOSUSPEND_DELAY); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_enable(&pdev->dev); + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) { + dev_err(&pdev->dev, "failed to resume SPI controller\n"); + goto err_rpm_put; + } + + ret = devm_spi_register_controller(&pdev->dev, sctlr); + if (ret) + goto err_rpm_put; + + pm_runtime_mark_last_busy(&pdev->dev); + pm_runtime_put_autosuspend(&pdev->dev); + + return 0; + +err_rpm_put: + pm_runtime_put_noidle(&pdev->dev); + pm_runtime_disable(&pdev->dev); +disable_clk: + clk_disable_unprepare(ss->clk); +free_controller: + spi_controller_put(sctlr); + + return ret; +} + +static int __exit sprd_spi_remove(struct platform_device *pdev) +{ + struct spi_controller *sctlr = platform_get_drvdata(pdev); + struct sprd_spi *ss = spi_controller_get_devdata(sctlr); + int ret; + + ret = pm_runtime_get_sync(ss->dev); + if (ret < 0) { + dev_err(ss->dev, "failed to resume SPI controller\n"); + return ret; + } + + clk_disable_unprepare(ss->clk); + pm_runtime_put_noidle(&pdev->dev); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +static int __maybe_unused sprd_spi_runtime_suspend(struct device *dev) +{ + struct spi_controller *sctlr = dev_get_drvdata(dev); + struct sprd_spi *ss = spi_controller_get_devdata(sctlr); + + clk_disable_unprepare(ss->clk); + + return 0; +} + +static int __maybe_unused sprd_spi_runtime_resume(struct device *dev) +{ + struct spi_controller *sctlr = dev_get_drvdata(dev); + struct sprd_spi *ss = spi_controller_get_devdata(sctlr); + int ret; + + ret = clk_prepare_enable(ss->clk); + if (ret) + return ret; + + sprd_spi_init_hw(ss); + return 0; +} + +static const struct dev_pm_ops sprd_spi_pm_ops = { + SET_RUNTIME_PM_OPS(sprd_spi_runtime_suspend, + sprd_spi_runtime_resume, NULL) +}; + +static const struct of_device_id sprd_spi_of_match[] = { + { .compatible = "sprd,sc9860-spi", }, + { /* sentinel */ } +}; + +static struct platform_driver sprd_spi_driver = { + .driver = { + .name = "sprd-spi", + .of_match_table = sprd_spi_of_match, + .pm = &sprd_spi_pm_ops, + }, + .probe = sprd_spi_probe, + .remove = sprd_spi_remove, +}; + +module_platform_driver(sprd_spi_driver); + +MODULE_DESCRIPTION("Spreadtrum SPI Controller driver"); +MODULE_AUTHOR("Lanqing Liu <lanqing.liu@spreadtrum.com>"); +MODULE_LICENSE("GPL v2");

[2/2] spi: sprd: Add SPI driver for Spreadtrum SC9860

Commit Message

Comments

Patch