aboutsummaryrefslogtreecommitdiff
path: root/drivers/spi
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-06-14 13:42:43 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-14 13:42:43 -0700
commit2cf4d4514d5b43c1f3b64bd0ec8b9853bde8f1dc (patch)
treee35a625496acc6ac852846d40b8851186b9d1ac4 /drivers/spi
parent44b7532b8b464f606053562400719c9c21276037 (diff)
parentce53895a5d24e0ee19fb92f56c17323fb4c9ab27 (diff)
Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (417 commits) MAINTAINERS: EB110ATX is not ebsa110 MAINTAINERS: update Eric Miao's email address and status fb: add support of LCD display controller on pxa168/910 (base layer) [ARM] 5552/1: ep93xx get_uart_rate(): use EP93XX_SYSCON_PWRCNT and EP93XX_SYSCON_PWRCN [ARM] pxa/sharpsl_pm: zaurus needs generic pxa suspend/resume routines [ARM] 5544/1: Trust PrimeCell resource sizes [ARM] pxa/sharpsl_pm: cleanup of gpio-related code. [ARM] pxa/sharpsl_pm: drop set_irq_type calls [ARM] pxa/sharpsl_pm: merge pxa-specific code into generic one [ARM] pxa/sharpsl_pm: merge the two sharpsl_pm.c since it's now pxa specific [ARM] sa1100: remove unused collie_pm.c [ARM] pxa: fix the conflicting non-static declarations of global_gpios[] [ARM] 5550/1: Add default configure file for w90p910 platform [ARM] 5549/1: Add clock api for w90p910 platform. [ARM] 5548/1: Add gpio api for w90p910 platform [ARM] 5551/1: Add multi-function pin api for w90p910 platform. [ARM] Make ARM_VIC_NR depend on ARM_VIC [ARM] 5546/1: ARM PL022 SSP/SPI driver v3 ARM: OMAP4: SMP: Update defconfig for OMAP4430 ARM: OMAP4: SMP: Enable SMP support for OMAP4430 ...
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/Kconfig11
-rw-r--r--drivers/spi/Makefile1
-rw-r--r--drivers/spi/amba-pl022.c1866
-rw-r--r--drivers/spi/spi_s3c24xx_gpio.c1
4 files changed, 1878 insertions, 1 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 95749477541..e8aae227b5e 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -118,7 +118,7 @@ config SPI_GPIO
config SPI_IMX
tristate "Freescale iMX SPI controller"
- depends on ARCH_IMX && EXPERIMENTAL
+ depends on ARCH_MX1 && EXPERIMENTAL
help
This enables using the Freescale iMX SPI controller in master
mode.
@@ -171,6 +171,15 @@ config SPI_ORION
help
This enables using the SPI master controller on the Orion chips.
+config SPI_PL022
+ tristate "ARM AMBA PL022 SSP controller (EXPERIMENTAL)"
+ depends on ARM_AMBA && EXPERIMENTAL
+ default y if MACH_U300
+ help
+ This selects the ARM(R) AMBA(R) PrimeCell PL022 SSP
+ controller. If you have an embedded system with an AMBA(R)
+ bus and a PL022 controller, say Y or M here.
+
config SPI_PXA2XX
tristate "PXA2xx SSP SPI master"
depends on ARCH_PXA && EXPERIMENTAL
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 5d0451936d8..ecfadb18048 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_SPI_PXA2XX) += pxa2xx_spi.o
obj-$(CONFIG_SPI_OMAP_UWIRE) += omap_uwire.o
obj-$(CONFIG_SPI_OMAP24XX) += omap2_mcspi.o
obj-$(CONFIG_SPI_ORION) += orion_spi.o
+obj-$(CONFIG_SPI_PL022) += amba-pl022.o
obj-$(CONFIG_SPI_MPC52xx_PSC) += mpc52xx_psc_spi.o
obj-$(CONFIG_SPI_MPC83xx) += spi_mpc83xx.o
obj-$(CONFIG_SPI_S3C24XX_GPIO) += spi_s3c24xx_gpio.o
diff --git a/drivers/spi/amba-pl022.c b/drivers/spi/amba-pl022.c
new file mode 100644
index 00000000000..da76797ce8b
--- /dev/null
+++ b/drivers/spi/amba-pl022.c
@@ -0,0 +1,1866 @@
+/*
+ * drivers/spi/amba-pl022.c
+ *
+ * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
+ *
+ * Copyright (C) 2008-2009 ST-Ericsson AB
+ * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
+ *
+ * Author: Linus Walleij <linus.walleij@stericsson.com>
+ *
+ * Initial version inspired by:
+ * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
+ * Initial adoption to PL022 by:
+ * Sachin Verma <sachin.verma@st.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+/*
+ * TODO:
+ * - add timeout on polled transfers
+ * - add generic DMA framework support
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/ioport.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/spi/spi.h>
+#include <linux/workqueue.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/amba/bus.h>
+#include <linux/amba/pl022.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+
+/*
+ * This macro is used to define some register default values.
+ * reg is masked with mask, the OR:ed with an (again masked)
+ * val shifted sb steps to the left.
+ */
+#define SSP_WRITE_BITS(reg, val, mask, sb) \
+ ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
+
+/*
+ * This macro is also used to define some default values.
+ * It will just shift val by sb steps to the left and mask
+ * the result with mask.
+ */
+#define GEN_MASK_BITS(val, mask, sb) \
+ (((val)<<(sb)) & (mask))
+
+#define DRIVE_TX 0
+#define DO_NOT_DRIVE_TX 1
+
+#define DO_NOT_QUEUE_DMA 0
+#define QUEUE_DMA 1
+
+#define RX_TRANSFER 1
+#define TX_TRANSFER 2
+
+/*
+ * Macros to access SSP Registers with their offsets
+ */
+#define SSP_CR0(r) (r + 0x000)
+#define SSP_CR1(r) (r + 0x004)
+#define SSP_DR(r) (r + 0x008)
+#define SSP_SR(r) (r + 0x00C)
+#define SSP_CPSR(r) (r + 0x010)
+#define SSP_IMSC(r) (r + 0x014)
+#define SSP_RIS(r) (r + 0x018)
+#define SSP_MIS(r) (r + 0x01C)
+#define SSP_ICR(r) (r + 0x020)
+#define SSP_DMACR(r) (r + 0x024)
+#define SSP_ITCR(r) (r + 0x080)
+#define SSP_ITIP(r) (r + 0x084)
+#define SSP_ITOP(r) (r + 0x088)
+#define SSP_TDR(r) (r + 0x08C)
+
+#define SSP_PID0(r) (r + 0xFE0)
+#define SSP_PID1(r) (r + 0xFE4)
+#define SSP_PID2(r) (r + 0xFE8)
+#define SSP_PID3(r) (r + 0xFEC)
+
+#define SSP_CID0(r) (r + 0xFF0)
+#define SSP_CID1(r) (r + 0xFF4)
+#define SSP_CID2(r) (r + 0xFF8)
+#define SSP_CID3(r) (r + 0xFFC)
+
+/*
+ * SSP Control Register 0 - SSP_CR0
+ */
+#define SSP_CR0_MASK_DSS (0x1FUL << 0)
+#define SSP_CR0_MASK_HALFDUP (0x1UL << 5)
+#define SSP_CR0_MASK_SPO (0x1UL << 6)
+#define SSP_CR0_MASK_SPH (0x1UL << 7)
+#define SSP_CR0_MASK_SCR (0xFFUL << 8)
+#define SSP_CR0_MASK_CSS (0x1FUL << 16)
+#define SSP_CR0_MASK_FRF (0x3UL << 21)
+
+/*
+ * SSP Control Register 0 - SSP_CR1
+ */
+#define SSP_CR1_MASK_LBM (0x1UL << 0)
+#define SSP_CR1_MASK_SSE (0x1UL << 1)
+#define SSP_CR1_MASK_MS (0x1UL << 2)
+#define SSP_CR1_MASK_SOD (0x1UL << 3)
+#define SSP_CR1_MASK_RENDN (0x1UL << 4)
+#define SSP_CR1_MASK_TENDN (0x1UL << 5)
+#define SSP_CR1_MASK_MWAIT (0x1UL << 6)
+#define SSP_CR1_MASK_RXIFLSEL (0x7UL << 7)
+#define SSP_CR1_MASK_TXIFLSEL (0x7UL << 10)
+
+/*
+ * SSP Data Register - SSP_DR
+ */
+#define SSP_DR_MASK_DATA 0xFFFFFFFF
+
+/*
+ * SSP Status Register - SSP_SR
+ */
+#define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
+#define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
+#define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
+#define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
+#define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
+
+/*
+ * SSP Clock Prescale Register - SSP_CPSR
+ */
+#define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
+
+/*
+ * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
+ */
+#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
+#define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
+#define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
+#define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
+
+/*
+ * SSP Raw Interrupt Status Register - SSP_RIS
+ */
+/* Receive Overrun Raw Interrupt status */
+#define SSP_RIS_MASK_RORRIS (0x1UL << 0)
+/* Receive Timeout Raw Interrupt status */
+#define SSP_RIS_MASK_RTRIS (0x1UL << 1)
+/* Receive FIFO Raw Interrupt status */
+#define SSP_RIS_MASK_RXRIS (0x1UL << 2)
+/* Transmit FIFO Raw Interrupt status */
+#define SSP_RIS_MASK_TXRIS (0x1UL << 3)
+
+/*
+ * SSP Masked Interrupt Status Register - SSP_MIS
+ */
+/* Receive Overrun Masked Interrupt status */
+#define SSP_MIS_MASK_RORMIS (0x1UL << 0)
+/* Receive Timeout Masked Interrupt status */
+#define SSP_MIS_MASK_RTMIS (0x1UL << 1)
+/* Receive FIFO Masked Interrupt status */
+#define SSP_MIS_MASK_RXMIS (0x1UL << 2)
+/* Transmit FIFO Masked Interrupt status */
+#define SSP_MIS_MASK_TXMIS (0x1UL << 3)
+
+/*
+ * SSP Interrupt Clear Register - SSP_ICR
+ */
+/* Receive Overrun Raw Clear Interrupt bit */
+#define SSP_ICR_MASK_RORIC (0x1UL << 0)
+/* Receive Timeout Clear Interrupt bit */
+#define SSP_ICR_MASK_RTIC (0x1UL << 1)
+
+/*
+ * SSP DMA Control Register - SSP_DMACR
+ */
+/* Receive DMA Enable bit */
+#define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
+/* Transmit DMA Enable bit */
+#define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
+
+/*
+ * SSP Integration Test control Register - SSP_ITCR
+ */
+#define SSP_ITCR_MASK_ITEN (0x1UL << 0)
+#define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
+
+/*
+ * SSP Integration Test Input Register - SSP_ITIP
+ */
+#define ITIP_MASK_SSPRXD (0x1UL << 0)
+#define ITIP_MASK_SSPFSSIN (0x1UL << 1)
+#define ITIP_MASK_SSPCLKIN (0x1UL << 2)
+#define ITIP_MASK_RXDMAC (0x1UL << 3)
+#define ITIP_MASK_TXDMAC (0x1UL << 4)
+#define ITIP_MASK_SSPTXDIN (0x1UL << 5)
+
+/*
+ * SSP Integration Test output Register - SSP_ITOP
+ */
+#define ITOP_MASK_SSPTXD (0x1UL << 0)
+#define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
+#define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
+#define ITOP_MASK_SSPOEn (0x1UL << 3)
+#define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
+#define ITOP_MASK_RORINTR (0x1UL << 5)
+#define ITOP_MASK_RTINTR (0x1UL << 6)
+#define ITOP_MASK_RXINTR (0x1UL << 7)
+#define ITOP_MASK_TXINTR (0x1UL << 8)
+#define ITOP_MASK_INTR (0x1UL << 9)
+#define ITOP_MASK_RXDMABREQ (0x1UL << 10)
+#define ITOP_MASK_RXDMASREQ (0x1UL << 11)
+#define ITOP_MASK_TXDMABREQ (0x1UL << 12)
+#define ITOP_MASK_TXDMASREQ (0x1UL << 13)
+
+/*
+ * SSP Test Data Register - SSP_TDR
+ */
+#define TDR_MASK_TESTDATA (0xFFFFFFFF)
+
+/*
+ * Message State
+ * we use the spi_message.state (void *) pointer to
+ * hold a single state value, that's why all this
+ * (void *) casting is done here.
+ */
+#define STATE_START ((void *) 0)
+#define STATE_RUNNING ((void *) 1)
+#define STATE_DONE ((void *) 2)
+#define STATE_ERROR ((void *) -1)
+
+/*
+ * Queue State
+ */
+#define QUEUE_RUNNING (0)
+#define QUEUE_STOPPED (1)
+/*
+ * SSP State - Whether Enabled or Disabled
+ */
+#define SSP_DISABLED (0)
+#define SSP_ENABLED (1)
+
+/*
+ * SSP DMA State - Whether DMA Enabled or Disabled
+ */
+#define SSP_DMA_DISABLED (0)
+#define SSP_DMA_ENABLED (1)
+
+/*
+ * SSP Clock Defaults
+ */
+#define NMDK_SSP_DEFAULT_CLKRATE 0x2
+#define NMDK_SSP_DEFAULT_PRESCALE 0x40
+
+/*
+ * SSP Clock Parameter ranges
+ */
+#define CPSDVR_MIN 0x02
+#define CPSDVR_MAX 0xFE
+#define SCR_MIN 0x00
+#define SCR_MAX 0xFF
+
+/*
+ * SSP Interrupt related Macros
+ */
+#define DEFAULT_SSP_REG_IMSC 0x0UL
+#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
+#define ENABLE_ALL_INTERRUPTS (~DEFAULT_SSP_REG_IMSC)
+
+#define CLEAR_ALL_INTERRUPTS 0x3
+
+
+/*
+ * The type of reading going on on this chip
+ */
+enum ssp_reading {
+ READING_NULL,
+ READING_U8,
+ READING_U16,
+ READING_U32
+};
+
+/**
+ * The type of writing going on on this chip
+ */
+enum ssp_writing {
+ WRITING_NULL,
+ WRITING_U8,
+ WRITING_U16,
+ WRITING_U32
+};
+
+/**
+ * struct vendor_data - vendor-specific config parameters
+ * for PL022 derivates
+ * @fifodepth: depth of FIFOs (both)
+ * @max_bpw: maximum number of bits per word
+ * @unidir: supports unidirection transfers
+ */
+struct vendor_data {
+ int fifodepth;
+ int max_bpw;
+ bool unidir;
+};
+
+/**
+ * struct pl022 - This is the private SSP driver data structure
+ * @adev: AMBA device model hookup
+ * @phybase: The physical memory where the SSP device resides
+ * @virtbase: The virtual memory where the SSP is mapped
+ * @master: SPI framework hookup
+ * @master_info: controller-specific data from machine setup
+ * @regs: SSP controller register's virtual address
+ * @pump_messages: Work struct for scheduling work to the workqueue
+ * @lock: spinlock to syncronise access to driver data
+ * @workqueue: a workqueue on which any spi_message request is queued
+ * @busy: workqueue is busy
+ * @run: workqueue is running
+ * @pump_transfers: Tasklet used in Interrupt Transfer mode
+ * @cur_msg: Pointer to current spi_message being processed
+ * @cur_transfer: Pointer to current spi_transfer
+ * @cur_chip: pointer to current clients chip(assigned from controller_state)
+ * @tx: current position in TX buffer to be read
+ * @tx_end: end position in TX buffer to be read
+ * @rx: current position in RX buffer to be written
+ * @rx_end: end position in RX buffer to be written
+ * @readingtype: the type of read currently going on
+ * @writingtype: the type or write currently going on
+ */
+struct pl022 {
+ struct amba_device *adev;
+ struct vendor_data *vendor;
+ resource_size_t phybase;
+ void __iomem *virtbase;
+ struct clk *clk;
+ struct spi_master *master;
+ struct pl022_ssp_controller *master_info;
+ /* Driver message queue */
+ struct workqueue_struct *workqueue;
+ struct work_struct pump_messages;
+ spinlock_t queue_lock;
+ struct list_head queue;
+ int busy;
+ int run;
+ /* Message transfer pump */
+ struct tasklet_struct pump_transfers;
+ struct spi_message *cur_msg;
+ struct spi_transfer *cur_transfer;
+ struct chip_data *cur_chip;
+ void *tx;
+ void *tx_end;
+ void *rx;
+ void *rx_end;
+ enum ssp_reading read;
+ enum ssp_writing write;
+};
+
+/**
+ * struct chip_data - To maintain runtime state of SSP for each client chip
+ * @cr0: Value of control register CR0 of SSP
+ * @cr1: Value of control register CR1 of SSP
+ * @dmacr: Value of DMA control Register of SSP
+ * @cpsr: Value of Clock prescale register
+ * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
+ * @enable_dma: Whether to enable DMA or not
+ * @write: function ptr to be used to write when doing xfer for this chip
+ * @read: function ptr to be used to read when doing xfer for this chip
+ * @cs_control: chip select callback provided by chip
+ * @xfer_type: polling/interrupt/DMA
+ *
+ * Runtime state of the SSP controller, maintained per chip,
+ * This would be set according to the current message that would be served
+ */
+struct chip_data {
+ u16 cr0;
+ u16 cr1;
+ u16 dmacr;
+ u16 cpsr;
+ u8 n_bytes;
+ u8 enable_dma:1;
+ enum ssp_reading read;
+ enum ssp_writing write;
+ void (*cs_control) (u32 command);
+ int xfer_type;
+};
+
+/**
+ * null_cs_control - Dummy chip select function
+ * @command: select/delect the chip
+ *
+ * If no chip select function is provided by client this is used as dummy
+ * chip select
+ */
+static void null_cs_control(u32 command)
+{
+ pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
+}
+
+/**
+ * giveback - current spi_message is over, schedule next message and call
+ * callback of this message. Assumes that caller already
+ * set message->status; dma and pio irqs are blocked
+ * @pl022: SSP driver private data structure
+ */
+static void giveback(struct pl022 *pl022)
+{
+ struct spi_transfer *last_transfer;
+ unsigned long flags;
+ struct spi_message *msg;
+ void (*curr_cs_control) (u32 command);
+
+ /*
+ * This local reference to the chip select function
+ * is needed because we set curr_chip to NULL
+ * as a step toward termininating the message.
+ */
+ curr_cs_control = pl022->cur_chip->cs_control;
+ spin_lock_irqsave(&pl022->queue_lock, flags);
+ msg = pl022->cur_msg;
+ pl022->cur_msg = NULL;
+ pl022->cur_transfer = NULL;
+ pl022->cur_chip = NULL;
+ queue_work(pl022->workqueue, &pl022->pump_messages);
+ spin_unlock_irqrestore(&pl022->queue_lock, flags);
+
+ last_transfer = list_entry(msg->transfers.prev,
+ struct spi_transfer,
+ transfer_list);
+
+ /* Delay if requested before any change in chip select */
+ if (last_transfer->delay_usecs)
+ /*
+ * FIXME: This runs in interrupt context.
+ * Is this really smart?
+ */
+ udelay(last_transfer->delay_usecs);
+
+ /*
+ * Drop chip select UNLESS cs_change is true or we are returning
+ * a message with an error, or next message is for another chip
+ */
+ if (!last_transfer->cs_change)
+ curr_cs_control(SSP_CHIP_DESELECT);
+ else {
+ struct spi_message *next_msg;
+
+ /* Holding of cs was hinted, but we need to make sure
+ * the next message is for the same chip. Don't waste
+ * time with the following tests unless this was hinted.
+ *
+ * We cannot postpone this until pump_messages, because
+ * after calling msg->complete (below) the driver that
+ * sent the current message could be unloaded, which
+ * could invalidate the cs_control() callback...
+ */
+
+ /* get a pointer to the next message, if any */
+ spin_lock_irqsave(&pl022->queue_lock, flags);
+ if (list_empty(&pl022->queue))
+ next_msg = NULL;
+ else
+ next_msg = list_entry(pl022->queue.next,
+ struct spi_message, queue);
+ spin_unlock_irqrestore(&pl022->queue_lock, flags);
+
+ /* see if the next and current messages point
+ * to the same chip
+ */
+ if (next_msg && next_msg->spi != msg->spi)
+ next_msg = NULL;
+ if (!next_msg || msg->state == STATE_ERROR)
+ curr_cs_control(SSP_CHIP_DESELECT);
+ }
+ msg->state = NULL;
+ if (msg->complete)
+ msg->complete(msg->context);
+ /* This message is completed, so let's turn off the clock! */
+ clk_disable(pl022->clk);
+}
+
+/**
+ * flush - flush the FIFO to reach a clean state
+ * @pl022: SSP driver private data structure
+ */
+static int flush(struct pl022 *pl022)
+{
+ unsigned long limit = loops_per_jiffy << 1;
+
+ dev_dbg(&pl022->adev->dev, "flush\n");
+ do {
+ while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
+ readw(SSP_DR(pl022->virtbase));
+ } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
+ return limit;
+}
+
+/**
+ * restore_state - Load configuration of current chip
+ * @pl022: SSP driver private data structure
+ */
+static void restore_state(struct pl022 *pl022)
+{
+ struct chip_data *chip = pl022->cur_chip;
+
+ writew(chip->cr0, SSP_CR0(pl022->virtbase));
+ writew(chip->cr1, SSP_CR1(pl022->virtbase));
+ writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
+ writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
+ writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
+ writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+}
+
+/**
+ * load_ssp_default_config - Load default configuration for SSP
+ * @pl022: SSP driver private data structure
+ */
+
+/*
+ * Default SSP Register Values
+ */
+#define DEFAULT_SSP_REG_CR0 ( \
+ GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
+ GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP, 5) | \
+ GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
+ GEN_MASK_BITS(SSP_CLK_FALLING_EDGE, SSP_CR0_MASK_SPH, 7) | \
+ GEN_MASK_BITS(NMDK_SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
+ GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS, 16) | \
+ GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 21) \
+)
+
+#define DEFAULT_SSP_REG_CR1 ( \
+ GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
+ GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
+ GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
+ GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
+ GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN, 4) | \
+ GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN, 5) | \
+ GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT, 6) |\
+ GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL, 7) | \
+ GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL, 10) \
+)
+
+#define DEFAULT_SSP_REG_CPSR ( \
+ GEN_MASK_BITS(NMDK_SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
+)
+
+#define DEFAULT_SSP_REG_DMACR (\
+ GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
+ GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
+)
+
+
+static void load_ssp_default_config(struct pl022 *pl022)
+{
+ writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
+ writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
+ writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
+ writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
+ writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
+ writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+}
+
+/**
+ * This will write to TX and read from RX according to the parameters
+ * set in pl022.
+ */
+static void readwriter(struct pl022 *pl022)
+{
+
+ /*
+ * The FIFO depth is different inbetween primecell variants.
+ * I believe filling in too much in the FIFO might cause
+ * errons in 8bit wide transfers on ARM variants (just 8 words
+ * FIFO, means only 8x8 = 64 bits in FIFO) at least.
+ *
+ * FIXME: currently we have no logic to account for this.
+ * perhaps there is even something broken in HW regarding
+ * 8bit transfers (it doesn't fail on 16bit) so this needs
+ * more investigation...
+ */
+ dev_dbg(&pl022->adev->dev,
+ "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
+ __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
+
+ /* Read as much as you can */
+ while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
+ && (pl022->rx < pl022->rx_end)) {
+ switch (pl022->read) {
+ case READING_NULL:
+ readw(SSP_DR(pl022->virtbase));
+ break;
+ case READING_U8:
+ *(u8 *) (pl022->rx) =
+ readw(SSP_DR(pl022->virtbase)) & 0xFFU;
+ break;
+ case READING_U16:
+ *(u16 *) (pl022->rx) =
+ (u16) readw(SSP_DR(pl022->virtbase));
+ break;
+ case READING_U32:
+ *(u32 *) (pl022->rx) =
+ readl(SSP_DR(pl022->virtbase));
+ break;
+ }
+ pl022->rx += (pl022->cur_chip->n_bytes);
+ }
+ /*
+ * Write as much as you can, while keeping an eye on the RX FIFO!
+ */
+ while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_TNF)
+ && (pl022->tx < pl022->tx_end)) {
+ switch (pl022->write) {
+ case WRITING_NULL:
+ writew(0x0, SSP_DR(pl022->virtbase));
+ break;
+ case WRITING_U8:
+ writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
+ break;
+ case WRITING_U16:
+ writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
+ break;
+ case WRITING_U32:
+ writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
+ break;
+ }
+ pl022->tx += (pl022->cur_chip->n_bytes);
+ /*
+ * This inner reader takes care of things appearing in the RX
+ * FIFO as we're transmitting. This will happen a lot since the
+ * clock starts running when you put things into the TX FIFO,
+ * and then things are continously clocked into the RX FIFO.
+ */
+ while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
+ && (pl022->rx < pl022->rx_end)) {
+ switch (pl022->read) {
+ case READING_NULL:
+ readw(SSP_DR(pl022->virtbase));
+ break;
+ case READING_U8:
+ *(u8 *) (pl022->rx) =
+ readw(SSP_DR(pl022->virtbase)) & 0xFFU;
+ break;
+ case READING_U16:
+ *(u16 *) (pl022->rx) =
+ (u16) readw(SSP_DR(pl022->virtbase));
+ break;
+ case READING_U32:
+ *(u32 *) (pl022->rx) =
+ readl(SSP_DR(pl022->virtbase));
+ break;
+ }
+ pl022->rx += (pl022->cur_chip->n_bytes);
+ }
+ }
+ /*
+ * When we exit here the TX FIFO should be full and the RX FIFO
+ * should be empty
+ */
+}
+
+
+/**
+ * next_transfer - Move to the Next transfer in the current spi message
+ * @pl022: SSP driver private data structure
+ *
+ * This function moves though the linked list of spi transfers in the
+ * current spi message and returns with the state of current spi
+ * message i.e whether its last transfer is done(STATE_DONE) or
+ * Next transfer is ready(STATE_RUNNING)
+ */
+static void *next_transfer(struct pl022 *pl022)
+{
+ struct spi_message *msg = pl022->cur_msg;
+ struct spi_transfer *trans = pl022->cur_transfer;
+
+ /* Move to next transfer */
+ if (trans->transfer_list.next != &msg->transfers) {
+ pl022->cur_transfer =
+ list_entry(trans->transfer_list.next,
+ struct spi_transfer, transfer_list);
+ return STATE_RUNNING;
+ }
+ return STATE_DONE;
+}
+/**
+ * pl022_interrupt_handler - Interrupt handler for SSP controller
+ *
+ * This function handles interrupts generated for an interrupt based transfer.
+ * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
+ * current message's state as STATE_ERROR and schedule the tasklet
+ * pump_transfers which will do the postprocessing of the current message by
+ * calling giveback(). Otherwise it reads data from RX FIFO till there is no
+ * more data, and writes data in TX FIFO till it is not full. If we complete
+ * the transfer we move to the next transfer and schedule the tasklet.
+ */
+static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
+{
+ struct pl022 *pl022 = dev_id;
+ struct spi_message *msg = pl022->cur_msg;
+ u16 irq_status = 0;
+ u16 flag = 0;
+
+ if (unlikely(!msg)) {
+ dev_err(&pl022->adev->dev,
+ "bad message state in interrupt handler");
+ /* Never fail */
+ return IRQ_HANDLED;
+ }
+
+ /* Read the Interrupt Status Register */
+ irq_status = readw(SSP_MIS(pl022->virtbase));
+
+ if (unlikely(!irq_status))
+ return IRQ_NONE;
+
+ /* This handles the error code interrupts */
+ if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
+ /*
+ * Overrun interrupt - bail out since our Data has been
+ * corrupted
+ */
+ dev_err(&pl022->adev->dev,
+ "FIFO overrun\n");
+ if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
+ dev_err(&pl022->adev->dev,
+ "RXFIFO is full\n");
+ if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_TNF)
+ dev_err(&pl022->adev->dev,
+ "TXFIFO is full\n");
+
+ /*
+ * Disable and clear interrupts, disable SSP,
+ * mark message with bad status so it can be
+ * retried.
+ */
+ writew(DISABLE_ALL_INTERRUPTS,
+ SSP_IMSC(pl022->virtbase));
+ writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+ writew((readw(SSP_CR1(pl022->virtbase)) &
+ (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
+ msg->state = STATE_ERROR;
+
+ /* Schedule message queue handler */
+ tasklet_schedule(&pl022->pump_transfers);
+ return IRQ_HANDLED;
+ }
+
+ readwriter(pl022);
+
+ if ((pl022->tx == pl022->tx_end) && (flag == 0)) {
+ flag = 1;
+ /* Disable Transmit interrupt */
+ writew(readw(SSP_IMSC(pl022->virtbase)) &
+ (~SSP_IMSC_MASK_TXIM),
+ SSP_IMSC(pl022->virtbase));
+ }
+
+ /*
+ * Since all transactions must write as much as shall be read,
+ * we can conclude the entire transaction once RX is complete.
+ * At this point, all TX will always be finished.
+ */
+ if (pl022->rx >= pl022->rx_end) {
+ writew(DISABLE_ALL_INTERRUPTS,
+ SSP_IMSC(pl022->virtbase));
+ writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+ if (unlikely(pl022->rx > pl022->rx_end)) {
+ dev_warn(&pl022->adev->dev, "read %u surplus "
+ "bytes (did you request an odd "
+ "number of bytes on a 16bit bus?)\n",
+ (u32) (pl022->rx - pl022->rx_end));
+ }
+ /* Update total bytes transfered */
+ msg->actual_length += pl022->cur_transfer->len;
+ if (pl022->cur_transfer->cs_change)
+ pl022->cur_chip->
+ cs_control(SSP_CHIP_DESELECT);
+ /* Move to next transfer */
+ msg->state = next_transfer(pl022);
+ tasklet_schedule(&pl022->pump_transfers);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * This sets up the pointers to memory for the next message to
+ * send out on the SPI bus.
+ */
+static int set_up_next_transfer(struct pl022 *pl022,
+ struct spi_transfer *transfer)
+{
+ int residue;
+
+ /* Sanity check the message for this bus width */
+ residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
+ if (unlikely(residue != 0)) {
+ dev_err(&pl022->adev->dev,
+ "message of %u bytes to transmit but the current "
+ "chip bus has a data width of %u bytes!\n",
+ pl022->cur_transfer->len,
+ pl022->cur_chip->n_bytes);
+ dev_err(&pl022->adev->dev, "skipping this message\n");
+ return -EIO;
+ }
+ pl022->tx = (void *)transfer->tx_buf;
+ pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
+ pl022->rx = (void *)transfer->rx_buf;
+ pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
+ pl022->write =
+ pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
+ pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
+ return 0;
+}
+
+/**
+ * pump_transfers - Tasklet function which schedules next interrupt transfer
+ * when running in interrupt transfer mode.
+ * @data: SSP driver private data structure
+ *
+ */
+static void pump_transfers(unsigned long data)
+{
+ struct pl022 *pl022 = (struct pl022 *) data;
+ struct spi_message *message = NULL;
+ struct spi_transfer *transfer = NULL;
+ struct spi_transfer *previous = NULL;
+
+ /* Get current state information */
+ message = pl022->cur_msg;
+ transfer = pl022->cur_transfer;
+
+ /* Handle for abort */
+ if (message->state == STATE_ERROR) {
+ message->status = -EIO;
+ giveback(pl022);
+ return;
+ }
+
+ /* Handle end of message */
+ if (message->state == STATE_DONE) {
+ message->status = 0;
+ giveback(pl022);
+ return;
+ }
+
+ /* Delay if requested at end of transfer before CS change */
+ if (message->state == STATE_RUNNING) {
+ previous = list_entry(transfer->transfer_list.prev,
+ struct spi_transfer,
+ transfer_list);
+ if (previous->delay_usecs)
+ /*
+ * FIXME: This runs in interrupt context.
+ * Is this really smart?
+ */
+ udelay(previous->delay_usecs);
+
+ /* Drop chip select only if cs_change is requested */
+ if (previous->cs_change)
+ pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
+ } else {
+ /* STATE_START */
+ message->state = STATE_RUNNING;
+ }
+
+ if (set_up_next_transfer(pl022, transfer)) {
+ message->state = STATE_ERROR;
+ message->status = -EIO;
+ giveback(pl022);
+ return;
+ }
+ /* Flush the FIFOs and let's go! */
+ flush(pl022);
+ writew(ENABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
+}
+
+/**
+ * NOT IMPLEMENTED
+ * configure_dma - It configures the DMA pipes for DMA transfers
+ * @data: SSP driver's private data structure
+ *
+ */
+static int configure_dma(void *data)
+{
+ struct pl022 *pl022 = data;
+ dev_dbg(&pl022->adev->dev, "configure DMA\n");
+ return -ENOTSUPP;
+}
+
+/**
+ * do_dma_transfer - It handles transfers of the current message
+ * if it is DMA xfer.
+ * NOT FULLY IMPLEMENTED
+ * @data: SSP driver's private data structure
+ */
+static void do_dma_transfer(void *data)
+{
+ struct pl022 *pl022 = data;
+
+ if (configure_dma(data)) {
+ dev_dbg(&pl022->adev->dev, "configuration of DMA Failed!\n");
+ goto err_config_dma;
+ }
+
+ /* TODO: Implememt DMA setup of pipes here */
+
+ /* Enable target chip, set up transfer */
+ pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
+ if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
+ /* Error path */
+ pl022->cur_msg->state = STATE_ERROR;
+ pl022->cur_msg->status = -EIO;
+ giveback(pl022);
+ return;
+ }
+ /* Enable SSP */
+ writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
+ SSP_CR1(pl022->virtbase));
+
+ /* TODO: Enable the DMA transfer here */
+ return;
+
+ err_config_dma:
+ pl022->cur_msg->state = STATE_ERROR;
+ pl022->cur_msg->status = -EIO;
+ giveback(pl022);
+ return;
+}
+
+static void do_interrupt_transfer(void *data)
+{
+ struct pl022 *pl022 = data;
+
+ /* Enable target chip */
+ pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
+ if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
+ /* Error path */
+ pl022->cur_msg->state = STATE_ERROR;
+ pl022->cur_msg->status = -EIO;
+ giveback(pl022);
+ return;
+ }
+ /* Enable SSP, turn on interrupts */
+ writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
+ SSP_CR1(pl022->virtbase));
+ writew(ENABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
+}
+
+static void do_polling_transfer(void *data)
+{
+ struct pl022 *pl022 = data;
+ struct spi_message *message = NULL;
+ struct spi_transfer *transfer = NULL;
+ struct spi_transfer *previous = NULL;
+ struct chip_data *chip;
+
+ chip = pl022->cur_chip;
+ message = pl022->cur_msg;
+
+ while (message->state != STATE_DONE) {
+ /* Handle for abort */
+ if (message->state == STATE_ERROR)
+ break;
+ transfer = pl022->cur_transfer;
+
+ /* Delay if requested at end of transfer */
+ if (message->state == STATE_RUNNING) {
+ previous =
+ list_entry(transfer->transfer_list.prev,
+ struct spi_transfer, transfer_list);
+ if (previous->delay_usecs)
+ udelay(previous->delay_usecs);
+ if (previous->cs_change)
+ pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
+ } else {
+ /* STATE_START */
+ message->state = STATE_RUNNING;
+ pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
+ }
+
+ /* Configuration Changing Per Transfer */