diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-06-14 13:42:43 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-06-14 13:42:43 -0700 |
commit | 2cf4d4514d5b43c1f3b64bd0ec8b9853bde8f1dc (patch) | |
tree | e35a625496acc6ac852846d40b8851186b9d1ac4 /drivers/spi | |
parent | 44b7532b8b464f606053562400719c9c21276037 (diff) | |
parent | ce53895a5d24e0ee19fb92f56c17323fb4c9ab27 (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/Kconfig | 11 | ||||
-rw-r--r-- | drivers/spi/Makefile | 1 | ||||
-rw-r--r-- | drivers/spi/amba-pl022.c | 1866 | ||||
-rw-r--r-- | drivers/spi/spi_s3c24xx_gpio.c | 1 |
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 */ |