-From e75df4f96373e5d16f8ca13aa031e54cdcfeda62 Mon Sep 17 00:00:00 2001
-From: John Crispin <blogic@openwrt.org>
-Date: Wed, 13 Mar 2013 09:29:37 +0100
-Subject: [PATCH 33/36] SPI: MIPS: lantiq: adds spi-xway
-
-This patch adds support for the SPI core found on several Lantiq SoCs.
-The Driver has been runtime tested in combination with m25p80 Flash Devices
-on Amazon_SE and VR9.
-
-Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
-Signed-off-by: John Crispin <blogic@openwrt.org>
----
- drivers/spi/Kconfig | 8 +
- drivers/spi/Makefile | 1 +
- drivers/spi/spi-xway.c | 977 ++++++++++++++++++++++++++++++++++++++++++++++++
- 3 files changed, 986 insertions(+)
- create mode 100644 drivers/spi/spi-xway.c
-
---- a/drivers/spi/Kconfig
-+++ b/drivers/spi/Kconfig
-@@ -626,6 +626,14 @@ config SPI_NUC900
- help
- SPI driver for Nuvoton NUC900 series ARM SoCs
-
-+config SPI_XWAY
-+ tristate "Lantiq SPI controller"
-+ depends on LANTIQ
-+ select SPI_BITBANG
-+ help
-+ This driver supports the Lantiq SoC SPI controller in master
-+ mode.
-+
- #
- # Add new SPI master controllers in alphabetical order above this line
- #
---- a/drivers/spi/Makefile
-+++ b/drivers/spi/Makefile
-@@ -90,3 +90,4 @@ obj-$(CONFIG_SPI_TXX9) += spi-txx9.o
- obj-$(CONFIG_SPI_XCOMM) += spi-xcomm.o
- obj-$(CONFIG_SPI_XILINX) += spi-xilinx.o
- obj-$(CONFIG_SPI_XTENSA_XTFPGA) += spi-xtensa-xtfpga.o
-+obj-$(CONFIG_SPI_XWAY) += spi-xway.o
---- /dev/null
-+++ b/drivers/spi/spi-xway.c
-@@ -0,0 +1,1003 @@
-+/*
-+ * Lantiq SoC SPI controller
-+ *
-+ * Copyright (C) 2011 Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
-+ * Copyright (C) 2012 John Crispin <blogic@openwrt.org>
-+ *
-+ * This program is free software; you can distribute it and/or modify it
-+ * under the terms of the GNU General Public License (Version 2) as
-+ * published by the Free Software Foundation.
-+ */
-+
-+#include <linux/init.h>
-+#include <linux/module.h>
-+#include <linux/workqueue.h>
-+#include <linux/platform_device.h>
-+#include <linux/io.h>
-+#include <linux/sched.h>
-+#include <linux/delay.h>
-+#include <linux/interrupt.h>
-+#include <linux/completion.h>
-+#include <linux/spinlock.h>
-+#include <linux/err.h>
-+#include <linux/clk.h>
-+#include <linux/spi/spi.h>
-+#include <linux/spi/spi_bitbang.h>
-+#include <linux/of_irq.h>
-+
-+#include <lantiq_soc.h>
-+
-+#define LTQ_SPI_CLC 0x00 /* Clock control */
-+#define LTQ_SPI_PISEL 0x04 /* Port input select */
-+#define LTQ_SPI_ID 0x08 /* Identification */
-+#define LTQ_SPI_CON 0x10 /* Control */
-+#define LTQ_SPI_STAT 0x14 /* Status */
-+#define LTQ_SPI_WHBSTATE 0x18 /* Write HW modified state */
-+#define LTQ_SPI_TB 0x20 /* Transmit buffer */
-+#define LTQ_SPI_RB 0x24 /* Receive buffer */
-+#define LTQ_SPI_RXFCON 0x30 /* Receive FIFO control */
-+#define LTQ_SPI_TXFCON 0x34 /* Transmit FIFO control */
-+#define LTQ_SPI_FSTAT 0x38 /* FIFO status */
-+#define LTQ_SPI_BRT 0x40 /* Baudrate timer */
-+#define LTQ_SPI_BRSTAT 0x44 /* Baudrate timer status */
-+#define LTQ_SPI_SFCON 0x60 /* Serial frame control */
-+#define LTQ_SPI_SFSTAT 0x64 /* Serial frame status */
-+#define LTQ_SPI_GPOCON 0x70 /* General purpose output control */
-+#define LTQ_SPI_GPOSTAT 0x74 /* General purpose output status */
-+#define LTQ_SPI_FGPO 0x78 /* Forced general purpose output */
-+#define LTQ_SPI_RXREQ 0x80 /* Receive request */
-+#define LTQ_SPI_RXCNT 0x84 /* Receive count */
-+#define LTQ_SPI_DMACON 0xEC /* DMA control */
-+#define LTQ_SPI_IRNEN 0xF4 /* Interrupt node enable */
-+#define LTQ_SPI_IRNICR 0xF8 /* Interrupt node interrupt capture */
-+#define LTQ_SPI_IRNCR 0xFC /* Interrupt node control */
-+
-+#define LTQ_SPI_CLC_SMC_SHIFT 16 /* Clock divider for sleep mode */
-+#define LTQ_SPI_CLC_SMC_MASK 0xFF
-+#define LTQ_SPI_CLC_RMC_SHIFT 8 /* Clock divider for normal run mode */
-+#define LTQ_SPI_CLC_RMC_MASK 0xFF
-+#define LTQ_SPI_CLC_DISS BIT(1) /* Disable status bit */
-+#define LTQ_SPI_CLC_DISR BIT(0) /* Disable request bit */
-+
-+#define LTQ_SPI_ID_TXFS_SHIFT 24 /* Implemented TX FIFO size */
-+#define LTQ_SPI_ID_TXFS_MASK 0x3F
-+#define LTQ_SPI_ID_RXFS_SHIFT 16 /* Implemented RX FIFO size */
-+#define LTQ_SPI_ID_RXFS_MASK 0x3F
-+#define LTQ_SPI_ID_REV_MASK 0x1F /* Hardware revision number */
-+#define LTQ_SPI_ID_CFG BIT(5) /* DMA interface support */
-+
-+#define LTQ_SPI_CON_BM_SHIFT 16 /* Data width selection */
-+#define LTQ_SPI_CON_BM_MASK 0x1F
-+#define LTQ_SPI_CON_EM BIT(24) /* Echo mode */
-+#define LTQ_SPI_CON_IDLE BIT(23) /* Idle bit value */
-+#define LTQ_SPI_CON_ENBV BIT(22) /* Enable byte valid control */
-+#define LTQ_SPI_CON_RUEN BIT(12) /* Receive underflow error enable */
-+#define LTQ_SPI_CON_TUEN BIT(11) /* Transmit underflow error enable */
-+#define LTQ_SPI_CON_AEN BIT(10) /* Abort error enable */
-+#define LTQ_SPI_CON_REN BIT(9) /* Receive overflow error enable */
-+#define LTQ_SPI_CON_TEN BIT(8) /* Transmit overflow error enable */
-+#define LTQ_SPI_CON_LB BIT(7) /* Loopback control */
-+#define LTQ_SPI_CON_PO BIT(6) /* Clock polarity control */
-+#define LTQ_SPI_CON_PH BIT(5) /* Clock phase control */
-+#define LTQ_SPI_CON_HB BIT(4) /* Heading control */
-+#define LTQ_SPI_CON_RXOFF BIT(1) /* Switch receiver off */
-+#define LTQ_SPI_CON_TXOFF BIT(0) /* Switch transmitter off */
-+
-+#define LTQ_SPI_STAT_RXBV_MASK 0x7
-+#define LTQ_SPI_STAT_RXBV_SHIFT 28
-+#define LTQ_SPI_STAT_BSY BIT(13) /* Busy flag */
-+#define LTQ_SPI_STAT_RUE BIT(12) /* Receive underflow error flag */
-+#define LTQ_SPI_STAT_TUE BIT(11) /* Transmit underflow error flag */
-+#define LTQ_SPI_STAT_AE BIT(10) /* Abort error flag */
-+#define LTQ_SPI_STAT_RE BIT(9) /* Receive error flag */
-+#define LTQ_SPI_STAT_TE BIT(8) /* Transmit error flag */
-+#define LTQ_SPI_STAT_MS BIT(1) /* Master/slave select bit */
-+#define LTQ_SPI_STAT_EN BIT(0) /* Enable bit */
-+
-+#define LTQ_SPI_WHBSTATE_SETTUE BIT(15) /* Set transmit underflow error flag */
-+#define LTQ_SPI_WHBSTATE_SETAE BIT(14) /* Set abort error flag */
-+#define LTQ_SPI_WHBSTATE_SETRE BIT(13) /* Set receive error flag */
-+#define LTQ_SPI_WHBSTATE_SETTE BIT(12) /* Set transmit error flag */
-+#define LTQ_SPI_WHBSTATE_CLRTUE BIT(11) /* Clear transmit underflow error
-+ flag */
-+#define LTQ_SPI_WHBSTATE_CLRAE BIT(10) /* Clear abort error flag */
-+#define LTQ_SPI_WHBSTATE_CLRRE BIT(9) /* Clear receive error flag */
-+#define LTQ_SPI_WHBSTATE_CLRTE BIT(8) /* Clear transmit error flag */
-+#define LTQ_SPI_WHBSTATE_SETME BIT(7) /* Set mode error flag */
-+#define LTQ_SPI_WHBSTATE_CLRME BIT(6) /* Clear mode error flag */
-+#define LTQ_SPI_WHBSTATE_SETRUE BIT(5) /* Set receive underflow error flag */
-+#define LTQ_SPI_WHBSTATE_CLRRUE BIT(4) /* Clear receive underflow error flag */
-+#define LTQ_SPI_WHBSTATE_SETMS BIT(3) /* Set master select bit */
-+#define LTQ_SPI_WHBSTATE_CLRMS BIT(2) /* Clear master select bit */
-+#define LTQ_SPI_WHBSTATE_SETEN BIT(1) /* Set enable bit (operational mode) */
-+#define LTQ_SPI_WHBSTATE_CLREN BIT(0) /* Clear enable bit (config mode */
-+#define LTQ_SPI_WHBSTATE_CLR_ERRORS 0x0F50
-+
-+#define LTQ_SPI_RXFCON_RXFITL_SHIFT 8 /* FIFO interrupt trigger level */
-+#define LTQ_SPI_RXFCON_RXFITL_MASK 0x3F
-+#define LTQ_SPI_RXFCON_RXFLU BIT(1) /* FIFO flush */
-+#define LTQ_SPI_RXFCON_RXFEN BIT(0) /* FIFO enable */
-+
-+#define LTQ_SPI_TXFCON_TXFITL_SHIFT 8 /* FIFO interrupt trigger level */
-+#define LTQ_SPI_TXFCON_TXFITL_MASK 0x3F
-+#define LTQ_SPI_TXFCON_TXFLU BIT(1) /* FIFO flush */
-+#define LTQ_SPI_TXFCON_TXFEN BIT(0) /* FIFO enable */
-+
-+#define LTQ_SPI_FSTAT_RXFFL_MASK 0x3f
-+#define LTQ_SPI_FSTAT_RXFFL_SHIFT 0
-+#define LTQ_SPI_FSTAT_TXFFL_MASK 0x3f
-+#define LTQ_SPI_FSTAT_TXFFL_SHIFT 8
-+
-+#define LTQ_SPI_GPOCON_ISCSBN_SHIFT 8
-+#define LTQ_SPI_GPOCON_INVOUTN_SHIFT 0
-+
-+#define LTQ_SPI_FGPO_SETOUTN_SHIFT 8
-+#define LTQ_SPI_FGPO_CLROUTN_SHIFT 0
-+
-+#define LTQ_SPI_RXREQ_RXCNT_MASK 0xFFFF /* Receive count value */
-+#define LTQ_SPI_RXCNT_TODO_MASK 0xFFFF /* Recevie to-do value */
-+
-+#define LTQ_SPI_IRNEN_F BIT(3) /* Frame end interrupt request */
-+#define LTQ_SPI_IRNEN_E BIT(2) /* Error end interrupt request */
-+#define LTQ_SPI_IRNEN_T BIT(0) /* Transmit end interrupt request */
-+#define LTQ_SPI_IRNEN_R BIT(1) /* Receive end interrupt request */
-+#define LTQ_SPI_IRNEN_T_XWAY BIT(1) /* Transmit end interrupt request */
-+#define LTQ_SPI_IRNEN_R_XWAY BIT(0) /* Receive end interrupt request */
-+#define LTQ_SPI_IRNEN_ALL 0xF
-+
-+struct ltq_spi {
-+ struct spi_bitbang bitbang;
-+ struct completion done;
-+ spinlock_t lock;
-+
-+ struct device *dev;
-+ void __iomem *base;
-+ struct clk *fpiclk;
-+ struct clk *spiclk;
-+
-+ int status;
-+ int irq[3];
-+
-+ const u8 *tx;
-+ u8 *rx;
-+ u32 tx_cnt;
-+ u32 rx_cnt;
-+ u32 len;
-+ struct spi_transfer *curr_transfer;
-+
-+ u32 (*get_tx) (struct ltq_spi *);
-+
-+ u16 txfs;
-+ u16 rxfs;
-+ unsigned dma_support:1;
-+ unsigned cfg_mode:1;
-+
-+ u32 irnen_t;
-+ u32 irnen_r;
-+};
-+
-+static inline struct ltq_spi *ltq_spi_to_hw(struct spi_device *spi)
-+{
-+ return spi_master_get_devdata(spi->master);
-+}
-+
-+static inline u32 ltq_spi_reg_read(struct ltq_spi *hw, u32 reg)
-+{
-+ return ioread32be(hw->base + reg);
-+}
-+
-+static inline void ltq_spi_reg_write(struct ltq_spi *hw, u32 val, u32 reg)
-+{
-+ iowrite32be(val, hw->base + reg);
-+}
-+
-+static inline void ltq_spi_reg_setbit(struct ltq_spi *hw, u32 bits, u32 reg)
-+{
-+ u32 val;
-+
-+ val = ltq_spi_reg_read(hw, reg);
-+ val |= bits;
-+ ltq_spi_reg_write(hw, val, reg);
-+}
-+
-+static inline void ltq_spi_reg_clearbit(struct ltq_spi *hw, u32 bits, u32 reg)
-+{
-+ u32 val;
-+
-+ val = ltq_spi_reg_read(hw, reg);
-+ val &= ~bits;
-+ ltq_spi_reg_write(hw, val, reg);
-+}
-+
-+static void ltq_spi_hw_enable(struct ltq_spi *hw)
-+{
-+ u32 clc;
-+
-+ /* Power-up module */
-+ clk_enable(hw->spiclk);
-+
-+ /*
-+ * Set clock divider for run mode to 1 to
-+ * run at same frequency as FPI bus
-+ */
-+ clc = (1 << LTQ_SPI_CLC_RMC_SHIFT);
-+ ltq_spi_reg_write(hw, clc, LTQ_SPI_CLC);
-+}
-+
-+static void ltq_spi_hw_disable(struct ltq_spi *hw)
-+{
-+ /* Set clock divider to 0 and set module disable bit */
-+ ltq_spi_reg_write(hw, LTQ_SPI_CLC_DISS, LTQ_SPI_CLC);
-+
-+ /* Power-down module */
-+ clk_disable(hw->spiclk);
-+}
-+
-+static void ltq_spi_reset_fifos(struct ltq_spi *hw)
-+{
-+ u32 val;
-+
-+ /*
-+ * Enable and flush FIFOs. Set interrupt trigger level to
-+ * half of FIFO count implemented in hardware.
-+ */
-+ if (hw->txfs > 1) {
-+ val = hw->txfs << (LTQ_SPI_TXFCON_TXFITL_SHIFT - 1);
-+ val |= LTQ_SPI_TXFCON_TXFEN | LTQ_SPI_TXFCON_TXFLU;
-+ ltq_spi_reg_write(hw, val, LTQ_SPI_TXFCON);
-+ }
-+
-+ if (hw->rxfs > 1) {
-+ val = hw->rxfs << (LTQ_SPI_RXFCON_RXFITL_SHIFT - 1);
-+ val |= LTQ_SPI_RXFCON_RXFEN | LTQ_SPI_RXFCON_RXFLU;
-+ ltq_spi_reg_write(hw, val, LTQ_SPI_RXFCON);
-+ }
-+}
-+
-+static inline int ltq_spi_wait_ready(struct ltq_spi *hw)
-+{
-+ u32 stat;
-+ unsigned long timeout;
-+
-+ timeout = jiffies + msecs_to_jiffies(200);
-+
-+ do {
-+ stat = ltq_spi_reg_read(hw, LTQ_SPI_STAT);
-+ if (!(stat & LTQ_SPI_STAT_BSY))
-+ return 0;
-+
-+ cond_resched();
-+ } while (!time_after_eq(jiffies, timeout));
-+
-+ dev_err(hw->dev, "SPI wait ready timed out stat: %x\n", stat);
-+
-+ return -ETIMEDOUT;
-+}
-+
-+static void ltq_spi_config_mode_set(struct ltq_spi *hw)
-+{
-+ if (hw->cfg_mode)
-+ return;
-+
-+ /*
-+ * Putting the SPI module in config mode is only safe if no
-+ * transfer is in progress as indicated by busy flag STATE.BSY.
-+ */
-+ if (ltq_spi_wait_ready(hw)) {
-+ ltq_spi_reset_fifos(hw);
-+ hw->status = -ETIMEDOUT;
-+ }
-+ ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_CLREN, LTQ_SPI_WHBSTATE);
-+
-+ hw->cfg_mode = 1;
-+}
-+
-+static void ltq_spi_run_mode_set(struct ltq_spi *hw)
-+{
-+ if (!hw->cfg_mode)
-+ return;
-+
-+ ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_SETEN, LTQ_SPI_WHBSTATE);
-+
-+ hw->cfg_mode = 0;
-+}
-+
-+static u32 ltq_spi_tx_word_u8(struct ltq_spi *hw)
-+{
-+ const u8 *tx = hw->tx;
-+ u32 data = *tx++;
-+
-+ hw->tx_cnt++;
-+ hw->tx++;
-+
-+ return data;
-+}
-+
-+static u32 ltq_spi_tx_word_u16(struct ltq_spi *hw)
-+{
-+ const u16 *tx = (u16 *) hw->tx;
-+ u32 data = *tx++;
-+
-+ hw->tx_cnt += 2;
-+ hw->tx += 2;
-+
-+ return data;
-+}
-+
-+static u32 ltq_spi_tx_word_u32(struct ltq_spi *hw)
-+{
-+ const u32 *tx = (u32 *) hw->tx;
-+ u32 data = *tx++;
-+
-+ hw->tx_cnt += 4;
-+ hw->tx += 4;
-+
-+ return data;
-+}
-+
-+static void ltq_spi_bits_per_word_set(struct spi_device *spi)
-+{
-+ struct ltq_spi *hw = ltq_spi_to_hw(spi);
-+ u32 bm;
-+ u8 bits_per_word = spi->bits_per_word;
-+
-+ /*
-+ * Use either default value of SPI device or value
-+ * from current transfer.
-+ */
-+ if (hw->curr_transfer && hw->curr_transfer->bits_per_word)
-+ bits_per_word = hw->curr_transfer->bits_per_word;
-+
-+ if (bits_per_word <= 8)
-+ hw->get_tx = ltq_spi_tx_word_u8;
-+ else if (bits_per_word <= 16)
-+ hw->get_tx = ltq_spi_tx_word_u16;
-+ else if (bits_per_word <= 32)
-+ hw->get_tx = ltq_spi_tx_word_u32;
-+
-+ /* CON.BM value = bits_per_word - 1 */
-+ bm = (bits_per_word - 1) << LTQ_SPI_CON_BM_SHIFT;
-+
-+ ltq_spi_reg_clearbit(hw, LTQ_SPI_CON_BM_MASK <<
-+ LTQ_SPI_CON_BM_SHIFT, LTQ_SPI_CON);
-+ ltq_spi_reg_setbit(hw, bm, LTQ_SPI_CON);
-+}
-+
-+static void ltq_spi_speed_set(struct spi_device *spi)
-+{
-+ struct ltq_spi *hw = ltq_spi_to_hw(spi);
-+ u32 br, max_speed_hz, spi_clk;
-+ u32 speed_hz = spi->max_speed_hz;
-+
-+ /*
-+ * Use either default value of SPI device or value
-+ * from current transfer.
-+ */
-+ if (hw->curr_transfer && hw->curr_transfer->speed_hz)
-+ speed_hz = hw->curr_transfer->speed_hz;
-+
-+ /*
-+ * SPI module clock is derived from FPI bus clock dependent on
-+ * divider value in CLC.RMS which is always set to 1.
-+ */
-+ spi_clk = clk_get_rate(hw->fpiclk);
-+
-+ /*
-+ * Maximum SPI clock frequency in master mode is half of
-+ * SPI module clock frequency. Maximum reload value of
-+ * baudrate generator BR is 2^16.
-+ */
-+ max_speed_hz = spi_clk / 2;
-+ if (speed_hz >= max_speed_hz)
-+ br = 0;
-+ else
-+ br = (max_speed_hz / speed_hz) - 1;
-+
-+ if (br > 0xFFFF)
-+ br = 0xFFFF;
-+
-+ ltq_spi_reg_write(hw, br, LTQ_SPI_BRT);
-+}
-+
-+static void ltq_spi_clockmode_set(struct spi_device *spi)
-+{
-+ struct ltq_spi *hw = ltq_spi_to_hw(spi);
-+ u32 con;
-+
-+ con = ltq_spi_reg_read(hw, LTQ_SPI_CON);
-+
-+ /*
-+ * SPI mode mapping in CON register:
-+ * Mode CPOL CPHA CON.PO CON.PH
-+ * 0 0 0 0 1
-+ * 1 0 1 0 0
-+ * 2 1 0 1 1
-+ * 3 1 1 1 0
-+ */
-+ if (spi->mode & SPI_CPHA)
-+ con &= ~LTQ_SPI_CON_PH;
-+ else
-+ con |= LTQ_SPI_CON_PH;
-+
-+ if (spi->mode & SPI_CPOL)
-+ con |= LTQ_SPI_CON_PO;
-+ else
-+ con &= ~LTQ_SPI_CON_PO;
-+
-+ /* Set heading control */
-+ if (spi->mode & SPI_LSB_FIRST)
-+ con &= ~LTQ_SPI_CON_HB;
-+ else
-+ con |= LTQ_SPI_CON_HB;
-+
-+ ltq_spi_reg_write(hw, con, LTQ_SPI_CON);
-+}
-+
-+static void ltq_spi_xmit_set(struct ltq_spi *hw, struct spi_transfer *t)
-+{
-+ u32 con;
-+
-+ con = ltq_spi_reg_read(hw, LTQ_SPI_CON);
-+
-+ if (t) {
-+ if (t->tx_buf && t->rx_buf) {
-+ con &= ~(LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF);
-+ } else if (t->rx_buf) {
-+ con &= ~LTQ_SPI_CON_RXOFF;
-+ con |= LTQ_SPI_CON_TXOFF;
-+ } else if (t->tx_buf) {
-+ con &= ~LTQ_SPI_CON_TXOFF;
-+ con |= LTQ_SPI_CON_RXOFF;
-+ }
-+ } else
-+ con |= (LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF);
-+
-+ ltq_spi_reg_write(hw, con, LTQ_SPI_CON);
-+}
-+
-+static void ltq_spi_internal_cs_activate(struct spi_device *spi)
-+{
-+ struct ltq_spi *hw = ltq_spi_to_hw(spi);
-+ u32 fgpo;
-+
-+ fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_CLROUTN_SHIFT));
-+ ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
-+}
-+
-+static void ltq_spi_internal_cs_deactivate(struct spi_device *spi)
-+{
-+ struct ltq_spi *hw = ltq_spi_to_hw(spi);
-+ u32 fgpo;
-+
-+ fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_SETOUTN_SHIFT));
-+ ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
-+}
-+
-+static void ltq_spi_chipselect(struct spi_device *spi, int cs)
-+{
-+ struct ltq_spi *hw = ltq_spi_to_hw(spi);
-+
-+ if (ltq_spi_wait_ready(hw))
-+ dev_err(&spi->dev, "wait failed\n");
-+
-+ switch (cs) {
-+ case BITBANG_CS_ACTIVE:
-+ ltq_spi_bits_per_word_set(spi);
-+ ltq_spi_speed_set(spi);
-+ ltq_spi_clockmode_set(spi);
-+ ltq_spi_run_mode_set(hw);
-+ ltq_spi_internal_cs_activate(spi);
-+ break;
-+
-+ case BITBANG_CS_INACTIVE:
-+ ltq_spi_internal_cs_deactivate(spi);
-+ ltq_spi_config_mode_set(hw);
-+ break;
-+ }
-+}
-+
-+static int ltq_spi_setup_transfer(struct spi_device *spi,
-+ struct spi_transfer *t)
-+{
-+ struct ltq_spi *hw = ltq_spi_to_hw(spi);
-+ u8 bits_per_word = spi->bits_per_word;
-+
-+ hw->curr_transfer = t;
-+
-+ if (t && t->bits_per_word)
-+ bits_per_word = t->bits_per_word;
-+
-+ if (bits_per_word > 32)
-+ return -EINVAL;
-+
-+ return 0;
-+}
-+
-+static int ltq_spi_setup(struct spi_device *spi)
-+{
-+ struct ltq_spi *hw = ltq_spi_to_hw(spi);
-+ u32 gpocon, fgpo;
-+
-+ /* Set default word length to 8 if not set */
-+ if (!spi->bits_per_word)
-+ spi->bits_per_word = 8;
-+
-+ if (spi->bits_per_word > 32)
-+ return -EINVAL;
-+
-+ /*
-+ * Up to six GPIOs can be connected to the SPI module
-+ * via GPIO alternate function to control the chip select lines.
-+ */
-+ gpocon = (1 << (spi->chip_select +
-+ LTQ_SPI_GPOCON_ISCSBN_SHIFT));
-+
-+ if (spi->mode & SPI_CS_HIGH)
-+ gpocon |= (1 << spi->chip_select);
-+
-+ fgpo = (1 << (spi->chip_select + LTQ_SPI_FGPO_SETOUTN_SHIFT));
-+
-+ ltq_spi_reg_setbit(hw, gpocon, LTQ_SPI_GPOCON);
-+ ltq_spi_reg_setbit(hw, fgpo, LTQ_SPI_FGPO);
-+
-+ return 0;
-+}
-+
-+static void ltq_spi_cleanup(struct spi_device *spi)
-+{
-+
-+}
-+
-+static void ltq_spi_txfifo_write(struct ltq_spi *hw)
-+{
-+ u32 fstat, data;
-+ u16 fifo_space;
-+
-+ /* Determine how much FIFOs are free for TX data */
-+ fstat = ltq_spi_reg_read(hw, LTQ_SPI_FSTAT);
-+ fifo_space = hw->txfs - ((fstat >> LTQ_SPI_FSTAT_TXFFL_SHIFT) &
-+ LTQ_SPI_FSTAT_TXFFL_MASK);
-+
-+ if (!fifo_space)
-+ return;
-+
-+ while (hw->tx_cnt < hw->len && fifo_space) {
-+ data = hw->get_tx(hw);
-+ ltq_spi_reg_write(hw, data, LTQ_SPI_TB);
-+ fifo_space--;
-+ }
-+}
-+
-+static void ltq_spi_rxfifo_read(struct ltq_spi *hw)
-+{
-+ u32 fstat, data, *rx32;
-+ u16 fifo_fill;
-+ u8 rxbv, shift, *rx8;
-+
-+ /* Determine how much FIFOs are filled with RX data */
-+ fstat = ltq_spi_reg_read(hw, LTQ_SPI_FSTAT);
-+ fifo_fill = ((fstat >> LTQ_SPI_FSTAT_RXFFL_SHIFT)
-+ & LTQ_SPI_FSTAT_RXFFL_MASK);
-+
-+ if (!fifo_fill)
-+ return;
-+
-+ /*
-+ * The 32 bit FIFO is always used completely independent from the
-+ * bits_per_word value. Thus four bytes have to be read at once
-+ * per FIFO.
-+ */
-+ rx32 = (u32 *) hw->rx;
-+ while (hw->len - hw->rx_cnt >= 4 && fifo_fill) {
-+ *rx32++ = ltq_spi_reg_read(hw, LTQ_SPI_RB);
-+ hw->rx_cnt += 4;
-+ hw->rx += 4;
-+ fifo_fill--;
-+ }
-+
-+ /*
-+ * If there are remaining bytes, read byte count from STAT.RXBV
-+ * register and read the data byte-wise.
-+ */
-+ while (fifo_fill && hw->rx_cnt < hw->len) {
-+ rxbv = (ltq_spi_reg_read(hw, LTQ_SPI_STAT) >>
-+ LTQ_SPI_STAT_RXBV_SHIFT) & LTQ_SPI_STAT_RXBV_MASK;
-+ data = ltq_spi_reg_read(hw, LTQ_SPI_RB);
-+
-+ shift = (rxbv - 1) * 8;
-+ rx8 = hw->rx;
-+
-+ while (rxbv) {
-+ *rx8++ = (data >> shift) & 0xFF;
-+ rxbv--;
-+ shift -= 8;
-+ hw->rx_cnt++;
-+ hw->rx++;
-+ }
-+
-+ fifo_fill--;
-+ }
-+}
-+
-+static void ltq_spi_rxreq_set(struct ltq_spi *hw)
-+{
-+ u32 rxreq, rxreq_max, rxtodo;
-+ u32 fstat, fifo_fill;
-+
-+ rxtodo = ltq_spi_reg_read(hw, LTQ_SPI_RXCNT) & LTQ_SPI_RXCNT_TODO_MASK;
-+
-+ /*
-+ * Check if there is remaining data in the FIFO before starting a new
-+ * receive request. The controller might have processed some more data
-+ * since the last FIFO poll.
-+ */
-+ fstat = ltq_spi_reg_read(hw, LTQ_SPI_FSTAT);
-+ fifo_fill = ((fstat >> LTQ_SPI_FSTAT_RXFFL_SHIFT)
-+ & LTQ_SPI_FSTAT_RXFFL_MASK);
-+ if (fifo_fill)
-+ return;
-+
-+ /*
-+ * In RX-only mode the serial clock is activated only after writing
-+ * the expected amount of RX bytes into RXREQ register.
-+ * To avoid receive overflows at high clocks it is better to request
-+ * only the amount of bytes that fits into all FIFOs. This value
-+ * depends on the FIFO size implemented in hardware.
-+ */
-+ rxreq = hw->len - hw->rx_cnt;
-+ rxreq_max = hw->rxfs << 2;
-+ rxreq = min(rxreq_max, rxreq);
-+
-+ if (!rxtodo && rxreq)
-+ ltq_spi_reg_write(hw, rxreq, LTQ_SPI_RXREQ);
-+}
-+
-+static inline void ltq_spi_complete(struct ltq_spi *hw)
-+{
-+ complete(&hw->done);
-+}
-+
-+irqreturn_t ltq_spi_tx_irq(int irq, void *data)
-+{
-+ struct ltq_spi *hw = data;
-+ unsigned long flags;
-+ int completed = 0;
-+
-+ spin_lock_irqsave(&hw->lock, flags);
-+
-+ if (hw->tx_cnt < hw->len)
-+ ltq_spi_txfifo_write(hw);
-+
-+ if (hw->tx_cnt == hw->len)
-+ completed = 1;
-+
-+ spin_unlock_irqrestore(&hw->lock, flags);
-+
-+ if (completed)
-+ ltq_spi_complete(hw);
-+
-+ return IRQ_HANDLED;
-+}
-+
-+irqreturn_t ltq_spi_rx_irq(int irq, void *data)
-+{
-+ struct ltq_spi *hw = data;
-+ unsigned long flags;
-+ int completed = 0;
-+
-+ spin_lock_irqsave(&hw->lock, flags);
-+
-+ if (hw->rx_cnt < hw->len) {
-+ ltq_spi_rxfifo_read(hw);
-+
-+ if (hw->tx && hw->tx_cnt < hw->len)
-+ ltq_spi_txfifo_write(hw);
-+ }
-+
-+ if (hw->rx_cnt == hw->len)
-+ completed = 1;
-+ else if (!hw->tx)
-+ ltq_spi_rxreq_set(hw);
-+
-+ spin_unlock_irqrestore(&hw->lock, flags);
-+
-+ if (completed)
-+ ltq_spi_complete(hw);
-+
-+ return IRQ_HANDLED;
-+}
-+
-+irqreturn_t ltq_spi_err_irq(int irq, void *data)
-+{
-+ struct ltq_spi *hw = data;
-+ unsigned long flags;
-+
-+ spin_lock_irqsave(&hw->lock, flags);
-+
-+ /* Disable all interrupts */
-+ ltq_spi_reg_clearbit(hw, LTQ_SPI_IRNEN_ALL, LTQ_SPI_IRNEN);
-+
-+ dev_err(hw->dev, "error %x\n", ltq_spi_reg_read(hw, LTQ_SPI_STAT));
-+
-+ /* Clear all error flags */
-+ ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_CLR_ERRORS, LTQ_SPI_WHBSTATE);
-+
-+ /* Flush FIFOs */
-+ ltq_spi_reg_setbit(hw, LTQ_SPI_RXFCON_RXFLU, LTQ_SPI_RXFCON);
-+ ltq_spi_reg_setbit(hw, LTQ_SPI_TXFCON_TXFLU, LTQ_SPI_TXFCON);
-+
-+ hw->status = -EIO;
-+ spin_unlock_irqrestore(&hw->lock, flags);
-+
-+ ltq_spi_complete(hw);
-+
-+ return IRQ_HANDLED;
-+}
-+
-+static int ltq_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
-+{
-+ struct ltq_spi *hw = ltq_spi_to_hw(spi);
-+ u32 irq_flags = 0;
-+
-+ hw->tx = t->tx_buf;
-+ hw->rx = t->rx_buf;
-+ hw->len = t->len;
-+ hw->tx_cnt = 0;
-+ hw->rx_cnt = 0;
-+ hw->status = 0;
-+ init_completion(&hw->done);
-+
-+ ltq_spi_xmit_set(hw, t);
-+
-+ /* Enable error interrupts */
-+ ltq_spi_reg_setbit(hw, LTQ_SPI_IRNEN_E, LTQ_SPI_IRNEN);
-+
-+ if (hw->tx) {
-+ /* Initially fill TX FIFO with as much data as possible */
-+ ltq_spi_txfifo_write(hw);
-+ irq_flags |= hw->irnen_t;
-+
-+ /* Always enable RX interrupt in Full Duplex mode */
-+ if (hw->rx)
-+ irq_flags |= hw->irnen_r;
-+ } else if (hw->rx) {
-+ /* Start RX clock */
-+ ltq_spi_rxreq_set(hw);
-+
-+ /* Enable RX interrupt to receive data from RX FIFOs */
-+ irq_flags |= hw->irnen_r;
-+ }
-+
-+ /* Enable TX or RX interrupts */
-+ ltq_spi_reg_setbit(hw, irq_flags, LTQ_SPI_IRNEN);
-+ wait_for_completion(&hw->done);
-+
-+ /* Disable all interrupts */
-+ ltq_spi_reg_clearbit(hw, LTQ_SPI_IRNEN_ALL, LTQ_SPI_IRNEN);
-+
-+ /*
-+ * Return length of current transfer for bitbang utility code if
-+ * no errors occured during transmission.
-+ */
-+ if (!hw->status)
-+ hw->status = hw->len;
-+
-+ return hw->status;
-+}
-+
-+static const struct ltq_spi_irq_map {
-+ char *name;
-+ irq_handler_t handler;
-+} ltq_spi_irqs[] = {
-+ { "spi_rx", ltq_spi_rx_irq },
-+ { "spi_tx", ltq_spi_tx_irq },
-+ { "spi_err", ltq_spi_err_irq },
-+};
-+
-+static int ltq_spi_probe(struct platform_device *pdev)
-+{
-+ struct resource irqres[3];
-+ struct spi_master *master;
-+ struct resource *r;
-+ struct ltq_spi *hw;
-+ int ret, i;
-+ u32 data, id;
-+
-+ if (of_irq_to_resource_table(pdev->dev.of_node, irqres, 3) != 3) {
-+ dev_err(&pdev->dev, "IRQ settings missing in device tree\n");
-+ return -EINVAL;
-+ }
-+
-+ master = spi_alloc_master(&pdev->dev, sizeof(struct ltq_spi));
-+ if (!master) {
-+ dev_err(&pdev->dev, "spi_alloc_master\n");
-+ ret = -ENOMEM;
-+ goto err;
-+ }
-+
-+ hw = spi_master_get_devdata(master);
-+
-+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-+ if (r == NULL) {
-+ dev_err(&pdev->dev, "platform_get_resource\n");
-+ ret = -ENOENT;
-+ goto err_master;
-+ }
-+
-+ r = devm_request_mem_region(&pdev->dev, r->start, resource_size(r),
-+ pdev->name);
-+ if (!r) {
-+ dev_err(&pdev->dev, "failed to request memory region\n");
-+ ret = -ENXIO;
-+ goto err_master;
-+ }
-+
-+ hw->base = devm_ioremap_nocache(&pdev->dev, r->start, resource_size(r));
-+ if (!hw->base) {
-+ dev_err(&pdev->dev, "failed to remap memory region\n");
-+ ret = -ENXIO;
-+ goto err_master;
-+ }
-+
-+ memset(hw->irq, 0, sizeof(hw->irq));
-+ for (i = 0; i < ARRAY_SIZE(ltq_spi_irqs); i++) {
-+ hw->irq[i] = irqres[i].start;
-+ ret = request_irq(hw->irq[i], ltq_spi_irqs[i].handler,
-+ 0, ltq_spi_irqs[i].name, hw);
-+ if (ret) {
-+ dev_err(&pdev->dev, "failed to request %s irq (%d)\n",
-+ ltq_spi_irqs[i].name, hw->irq[i]);
-+ goto err_irq;
-+ }
-+ }
-+
-+ hw->fpiclk = clk_get_fpi();
-+ if (IS_ERR(hw->fpiclk)) {
-+ dev_err(&pdev->dev, "failed to get fpi clock\n");
-+ ret = PTR_ERR(hw->fpiclk);
-+ goto err_clk;
-+ }
-+
-+ hw->spiclk = clk_get(&pdev->dev, NULL);
-+ if (IS_ERR(hw->spiclk)) {
-+ dev_err(&pdev->dev, "failed to get spi clock gate\n");
-+ ret = PTR_ERR(hw->spiclk);
-+ goto err_clk;
-+ }
-+
-+ hw->bitbang.master = spi_master_get(master);
-+ hw->bitbang.chipselect = ltq_spi_chipselect;
-+ hw->bitbang.setup_transfer = ltq_spi_setup_transfer;
-+ hw->bitbang.txrx_bufs = ltq_spi_txrx_bufs;
-+
-+ if (of_machine_is_compatible("lantiq,ase")) {
-+ master->num_chipselect = 3;
-+
-+ hw->irnen_t = LTQ_SPI_IRNEN_T_XWAY;
-+ hw->irnen_r = LTQ_SPI_IRNEN_R_XWAY;
-+ } else {
-+ master->num_chipselect = 6;
-+
-+ hw->irnen_t = LTQ_SPI_IRNEN_T;
-+ hw->irnen_r = LTQ_SPI_IRNEN_R;
-+ }
-+
-+ master->bus_num = pdev->id;
-+ master->setup = ltq_spi_setup;
-+ master->cleanup = ltq_spi_cleanup;
-+ master->dev.of_node = pdev->dev.of_node;
-+
-+ hw->dev = &pdev->dev;
-+ init_completion(&hw->done);
-+ spin_lock_init(&hw->lock);
-+
-+ ltq_spi_hw_enable(hw);
-+
-+ /* Read module capabilities */
-+ id = ltq_spi_reg_read(hw, LTQ_SPI_ID);
-+ hw->txfs = (id >> LTQ_SPI_ID_TXFS_SHIFT) & LTQ_SPI_ID_TXFS_MASK;
-+ hw->rxfs = (id >> LTQ_SPI_ID_RXFS_SHIFT) & LTQ_SPI_ID_RXFS_MASK;
-+ hw->dma_support = (id & LTQ_SPI_ID_CFG) ? 1 : 0;
-+
-+ ltq_spi_config_mode_set(hw);
-+
-+ /* Enable error checking, disable TX/RX, set idle value high */
-+ data = LTQ_SPI_CON_RUEN | LTQ_SPI_CON_AEN |
-+ LTQ_SPI_CON_TEN | LTQ_SPI_CON_REN |
-+ LTQ_SPI_CON_TXOFF | LTQ_SPI_CON_RXOFF | LTQ_SPI_CON_IDLE;
-+ ltq_spi_reg_write(hw, data, LTQ_SPI_CON);
-+
-+ /* Enable master mode and clear error flags */
-+ ltq_spi_reg_write(hw, LTQ_SPI_WHBSTATE_SETMS |
-+ LTQ_SPI_WHBSTATE_CLR_ERRORS, LTQ_SPI_WHBSTATE);
-+
-+ /* Reset GPIO/CS registers */
-+ ltq_spi_reg_write(hw, 0x0, LTQ_SPI_GPOCON);
-+ ltq_spi_reg_write(hw, 0xFF00, LTQ_SPI_FGPO);
-+
-+ /* Enable and flush FIFOs */
-+ ltq_spi_reset_fifos(hw);
-+
-+ ret = spi_bitbang_start(&hw->bitbang);
-+ if (ret) {
-+ dev_err(&pdev->dev, "spi_bitbang_start failed\n");
-+ goto err_bitbang;
-+ }
-+
-+ platform_set_drvdata(pdev, hw);
-+
-+ pr_info("Lantiq SoC SPI controller rev %u (TXFS %u, RXFS %u, DMA %u)\n",
-+ id & LTQ_SPI_ID_REV_MASK, hw->txfs, hw->rxfs, hw->dma_support);
-+
-+ return 0;
-+
-+err_bitbang:
-+ ltq_spi_hw_disable(hw);
-+
-+err_clk:
-+ if (hw->fpiclk)
-+ clk_put(hw->fpiclk);
-+ if (hw->spiclk)
-+ clk_put(hw->spiclk);
-+
-+err_irq:
-+ clk_put(hw->fpiclk);
-+
-+ for (; i > 0; i--)
-+ free_irq(hw->irq[i], hw);
-+
-+err_master:
-+ spi_master_put(master);
-+
-+err:
-+ return ret;
-+}
-+
-+static int ltq_spi_remove(struct platform_device *pdev)
-+{
-+ struct ltq_spi *hw = platform_get_drvdata(pdev);
-+ int i;
-+
-+ spi_bitbang_stop(&hw->bitbang);
-+
-+ platform_set_drvdata(pdev, NULL);
-+
-+ ltq_spi_config_mode_set(hw);
-+ ltq_spi_hw_disable(hw);
-+
-+ for (i = 0; i < ARRAY_SIZE(hw->irq); i++)
-+ if (0 < hw->irq[i])
-+ free_irq(hw->irq[i], hw);
-+
-+ if (hw->fpiclk)
-+ clk_put(hw->fpiclk);
-+ if (hw->spiclk)
-+ clk_put(hw->spiclk);
-+
-+ spi_master_put(hw->bitbang.master);
-+
-+ return 0;
-+}
-+
-+static const struct of_device_id ltq_spi_match[] = {
-+ { .compatible = "lantiq,spi-xway" },
-+ {},
-+};
-+MODULE_DEVICE_TABLE(of, ltq_spi_match);
-+
-+static struct platform_driver ltq_spi_driver = {
-+ .probe = ltq_spi_probe,
-+ .remove = ltq_spi_remove,
-+ .driver = {
-+ .name = "spi-xway",
-+ .owner = THIS_MODULE,
-+ .of_match_table = ltq_spi_match,
-+ },
-+};
-+
-+module_platform_driver(ltq_spi_driver);
-+
-+MODULE_DESCRIPTION("Lantiq SoC SPI controller driver");
-+MODULE_AUTHOR("Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>");
-+MODULE_LICENSE("GPL");
-+MODULE_ALIAS("platform:spi-xway");
projects / openwrt / openwrt.git / commitdiff