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linux-sg2042/drivers/spi/spi-pxa2xx.c

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/*
* Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
* Copyright (C) 2013, Intel Corporation
*
* 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.
*/
#include <linux/bitops.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/ioport.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/spi/pxa2xx_spi.h>
#include <linux/spi/spi.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/pm_runtime.h>
#include <linux/acpi.h>
#include <linux/of_device.h>
#include "spi-pxa2xx.h"
MODULE_AUTHOR("Stephen Street");
MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pxa2xx-spi");
#define TIMOUT_DFLT 1000
/*
* for testing SSCR1 changes that require SSP restart, basically
* everything except the service and interrupt enables, the pxa270 developer
* manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this
* list, but the PXA255 dev man says all bits without really meaning the
* service and interrupt enables
*/
#define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
| SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
| SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
| SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
| SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
#define QUARK_X1000_SSCR1_CHANGE_MASK (QUARK_X1000_SSCR1_STRF \
| QUARK_X1000_SSCR1_EFWR \
| QUARK_X1000_SSCR1_RFT \
| QUARK_X1000_SSCR1_TFT \
| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
#define CE4100_SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
| SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
| SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
| SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
| CE4100_SSCR1_RFT | CE4100_SSCR1_TFT | SSCR1_MWDS \
| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
#define LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24)
#define LPSS_CS_CONTROL_SW_MODE BIT(0)
#define LPSS_CS_CONTROL_CS_HIGH BIT(1)
#define LPSS_CAPS_CS_EN_SHIFT 9
#define LPSS_CAPS_CS_EN_MASK (0xf << LPSS_CAPS_CS_EN_SHIFT)
struct lpss_config {
/* LPSS offset from drv_data->ioaddr */
unsigned offset;
/* Register offsets from drv_data->lpss_base or -1 */
int reg_general;
int reg_ssp;
int reg_cs_ctrl;
int reg_capabilities;
/* FIFO thresholds */
u32 rx_threshold;
u32 tx_threshold_lo;
u32 tx_threshold_hi;
/* Chip select control */
unsigned cs_sel_shift;
unsigned cs_sel_mask;
unsigned cs_num;
};
/* Keep these sorted with enum pxa_ssp_type */
static const struct lpss_config lpss_platforms[] = {
{ /* LPSS_LPT_SSP */
.offset = 0x800,
.reg_general = 0x08,
.reg_ssp = 0x0c,
.reg_cs_ctrl = 0x18,
.reg_capabilities = -1,
.rx_threshold = 64,
.tx_threshold_lo = 160,
.tx_threshold_hi = 224,
},
{ /* LPSS_BYT_SSP */
.offset = 0x400,
.reg_general = 0x08,
.reg_ssp = 0x0c,
.reg_cs_ctrl = 0x18,
.reg_capabilities = -1,
.rx_threshold = 64,
.tx_threshold_lo = 160,
.tx_threshold_hi = 224,
},
{ /* LPSS_BSW_SSP */
.offset = 0x400,
.reg_general = 0x08,
.reg_ssp = 0x0c,
.reg_cs_ctrl = 0x18,
.reg_capabilities = -1,
.rx_threshold = 64,
.tx_threshold_lo = 160,
.tx_threshold_hi = 224,
.cs_sel_shift = 2,
.cs_sel_mask = 1 << 2,
.cs_num = 2,
},
{ /* LPSS_SPT_SSP */
.offset = 0x200,
.reg_general = -1,
.reg_ssp = 0x20,
.reg_cs_ctrl = 0x24,
.reg_capabilities = -1,
.rx_threshold = 1,
.tx_threshold_lo = 32,
.tx_threshold_hi = 56,
},
{ /* LPSS_BXT_SSP */
.offset = 0x200,
.reg_general = -1,
.reg_ssp = 0x20,
.reg_cs_ctrl = 0x24,
.reg_capabilities = 0xfc,
.rx_threshold = 1,
.tx_threshold_lo = 16,
.tx_threshold_hi = 48,
.cs_sel_shift = 8,
.cs_sel_mask = 3 << 8,
},
{ /* LPSS_CNL_SSP */
.offset = 0x200,
.reg_general = -1,
.reg_ssp = 0x20,
.reg_cs_ctrl = 0x24,
.reg_capabilities = 0xfc,
.rx_threshold = 1,
.tx_threshold_lo = 32,
.tx_threshold_hi = 56,
.cs_sel_shift = 8,
.cs_sel_mask = 3 << 8,
},
};
static inline const struct lpss_config
*lpss_get_config(const struct driver_data *drv_data)
{
return &lpss_platforms[drv_data->ssp_type - LPSS_LPT_SSP];
}
static bool is_lpss_ssp(const struct driver_data *drv_data)
{
switch (drv_data->ssp_type) {
case LPSS_LPT_SSP:
case LPSS_BYT_SSP:
case LPSS_BSW_SSP:
case LPSS_SPT_SSP:
case LPSS_BXT_SSP:
case LPSS_CNL_SSP:
return true;
default:
return false;
}
}
static bool is_quark_x1000_ssp(const struct driver_data *drv_data)
{
return drv_data->ssp_type == QUARK_X1000_SSP;
}
static u32 pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data *drv_data)
{
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
return QUARK_X1000_SSCR1_CHANGE_MASK;
case CE4100_SSP:
return CE4100_SSCR1_CHANGE_MASK;
default:
return SSCR1_CHANGE_MASK;
}
}
static u32
pxa2xx_spi_get_rx_default_thre(const struct driver_data *drv_data)
{
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
return RX_THRESH_QUARK_X1000_DFLT;
case CE4100_SSP:
return RX_THRESH_CE4100_DFLT;
default:
return RX_THRESH_DFLT;
}
}
static bool pxa2xx_spi_txfifo_full(const struct driver_data *drv_data)
{
u32 mask;
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
mask = QUARK_X1000_SSSR_TFL_MASK;
break;
case CE4100_SSP:
mask = CE4100_SSSR_TFL_MASK;
break;
default:
mask = SSSR_TFL_MASK;
break;
}
return (pxa2xx_spi_read(drv_data, SSSR) & mask) == mask;
}
static void pxa2xx_spi_clear_rx_thre(const struct driver_data *drv_data,
u32 *sccr1_reg)
{
u32 mask;
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
mask = QUARK_X1000_SSCR1_RFT;
break;
case CE4100_SSP:
mask = CE4100_SSCR1_RFT;
break;
default:
mask = SSCR1_RFT;
break;
}
*sccr1_reg &= ~mask;
}
static void pxa2xx_spi_set_rx_thre(const struct driver_data *drv_data,
u32 *sccr1_reg, u32 threshold)
{
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
*sccr1_reg |= QUARK_X1000_SSCR1_RxTresh(threshold);
break;
case CE4100_SSP:
*sccr1_reg |= CE4100_SSCR1_RxTresh(threshold);
break;
default:
*sccr1_reg |= SSCR1_RxTresh(threshold);
break;
}
}
static u32 pxa2xx_configure_sscr0(const struct driver_data *drv_data,
u32 clk_div, u8 bits)
{
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
return clk_div
| QUARK_X1000_SSCR0_Motorola
| QUARK_X1000_SSCR0_DataSize(bits > 32 ? 8 : bits)
| SSCR0_SSE;
default:
return clk_div
| SSCR0_Motorola
| SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
| SSCR0_SSE
| (bits > 16 ? SSCR0_EDSS : 0);
}
}
/*
* Read and write LPSS SSP private registers. Caller must first check that
* is_lpss_ssp() returns true before these can be called.
*/
static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
{
WARN_ON(!drv_data->lpss_base);
return readl(drv_data->lpss_base + offset);
}
static void __lpss_ssp_write_priv(struct driver_data *drv_data,
unsigned offset, u32 value)
{
WARN_ON(!drv_data->lpss_base);
writel(value, drv_data->lpss_base + offset);
}
/*
* lpss_ssp_setup - perform LPSS SSP specific setup
* @drv_data: pointer to the driver private data
*
* Perform LPSS SSP specific setup. This function must be called first if
* one is going to use LPSS SSP private registers.
*/
static void lpss_ssp_setup(struct driver_data *drv_data)
{
const struct lpss_config *config;
u32 value;
config = lpss_get_config(drv_data);
drv_data->lpss_base = drv_data->ioaddr + config->offset;
/* Enable software chip select control */
value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
value &= ~(LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH);
value |= LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH;
__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
/* Enable multiblock DMA transfers */
if (drv_data->master_info->enable_dma) {
__lpss_ssp_write_priv(drv_data, config->reg_ssp, 1);
if (config->reg_general >= 0) {
value = __lpss_ssp_read_priv(drv_data,
config->reg_general);
value |= LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE;
__lpss_ssp_write_priv(drv_data,
config->reg_general, value);
}
}
}
static void lpss_ssp_select_cs(struct spi_device *spi,
const struct lpss_config *config)
{
struct driver_data *drv_data =
spi_controller_get_devdata(spi->controller);
u32 value, cs;
if (!config->cs_sel_mask)
return;
value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
cs = spi->chip_select;
cs <<= config->cs_sel_shift;
if (cs != (value & config->cs_sel_mask)) {
/*
* When switching another chip select output active the
* output must be selected first and wait 2 ssp_clk cycles
* before changing state to active. Otherwise a short
* glitch will occur on the previous chip select since
* output select is latched but state control is not.
*/
value &= ~config->cs_sel_mask;
value |= cs;
__lpss_ssp_write_priv(drv_data,
config->reg_cs_ctrl, value);
ndelay(1000000000 /
(drv_data->master->max_speed_hz / 2));
}
}
static void lpss_ssp_cs_control(struct spi_device *spi, bool enable)
{
struct driver_data *drv_data =
spi_controller_get_devdata(spi->controller);
const struct lpss_config *config;
u32 value;
config = lpss_get_config(drv_data);
if (enable)
lpss_ssp_select_cs(spi, config);
value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
if (enable)
value &= ~LPSS_CS_CONTROL_CS_HIGH;
else
value |= LPSS_CS_CONTROL_CS_HIGH;
__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
}
static void cs_assert(struct spi_device *spi)
{
struct chip_data *chip = spi_get_ctldata(spi);
struct driver_data *drv_data =
spi_controller_get_devdata(spi->controller);
if (drv_data->ssp_type == CE4100_SSP) {
pxa2xx_spi_write(drv_data, SSSR, chip->frm);
return;
}
if (chip->cs_control) {
chip->cs_control(PXA2XX_CS_ASSERT);
return;
}
if (chip->gpiod_cs) {
gpiod_set_value(chip->gpiod_cs, chip->gpio_cs_inverted);
return;
}
if (is_lpss_ssp(drv_data))
lpss_ssp_cs_control(spi, true);
}
static void cs_deassert(struct spi_device *spi)
{
struct chip_data *chip = spi_get_ctldata(spi);
struct driver_data *drv_data =
spi_controller_get_devdata(spi->controller);
unsigned long timeout;
if (drv_data->ssp_type == CE4100_SSP)
return;
/* Wait until SSP becomes idle before deasserting the CS */
timeout = jiffies + msecs_to_jiffies(10);
while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY &&
!time_after(jiffies, timeout))
cpu_relax();
if (chip->cs_control) {
chip->cs_control(PXA2XX_CS_DEASSERT);
return;
}
if (chip->gpiod_cs) {
gpiod_set_value(chip->gpiod_cs, !chip->gpio_cs_inverted);
return;
}
if (is_lpss_ssp(drv_data))
lpss_ssp_cs_control(spi, false);
}
static void pxa2xx_spi_set_cs(struct spi_device *spi, bool level)
{
if (level)
cs_deassert(spi);
else
cs_assert(spi);
}
int pxa2xx_spi_flush(struct driver_data *drv_data)
{
unsigned long limit = loops_per_jiffy << 1;
do {
while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
pxa2xx_spi_read(drv_data, SSDR);
} while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY) && --limit);
write_SSSR_CS(drv_data, SSSR_ROR);
return limit;
}
static int null_writer(struct driver_data *drv_data)
{
u8 n_bytes = drv_data->n_bytes;
if (pxa2xx_spi_txfifo_full(drv_data)
|| (drv_data->tx == drv_data->tx_end))
return 0;
pxa2xx_spi_write(drv_data, SSDR, 0);
drv_data->tx += n_bytes;
return 1;
}
static int null_reader(struct driver_data *drv_data)
{
u8 n_bytes = drv_data->n_bytes;
while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
&& (drv_data->rx < drv_data->rx_end)) {
pxa2xx_spi_read(drv_data, SSDR);
drv_data->rx += n_bytes;
}
return drv_data->rx == drv_data->rx_end;
}
static int u8_writer(struct driver_data *drv_data)
{
if (pxa2xx_spi_txfifo_full(drv_data)
|| (drv_data->tx == drv_data->tx_end))
return 0;
pxa2xx_spi_write(drv_data, SSDR, *(u8 *)(drv_data->tx));
++drv_data->tx;
return 1;
}
static int u8_reader(struct driver_data *drv_data)
{
while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
&& (drv_data->rx < drv_data->rx_end)) {
*(u8 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
++drv_data->rx;
}
return drv_data->rx == drv_data->rx_end;
}
static int u16_writer(struct driver_data *drv_data)
{
if (pxa2xx_spi_txfifo_full(drv_data)
|| (drv_data->tx == drv_data->tx_end))
return 0;
pxa2xx_spi_write(drv_data, SSDR, *(u16 *)(drv_data->tx));
drv_data->tx += 2;
return 1;
}
static int u16_reader(struct driver_data *drv_data)
{
while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
&& (drv_data->rx < drv_data->rx_end)) {
*(u16 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
drv_data->rx += 2;
}
return drv_data->rx == drv_data->rx_end;
}
static int u32_writer(struct driver_data *drv_data)
{
if (pxa2xx_spi_txfifo_full(drv_data)
|| (drv_data->tx == drv_data->tx_end))
return 0;
pxa2xx_spi_write(drv_data, SSDR, *(u32 *)(drv_data->tx));
drv_data->tx += 4;
return 1;
}
static int u32_reader(struct driver_data *drv_data)
{
while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
&& (drv_data->rx < drv_data->rx_end)) {
*(u32 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
drv_data->rx += 4;
}
return drv_data->rx == drv_data->rx_end;
}
static void reset_sccr1(struct driver_data *drv_data)
{
struct chip_data *chip =
spi_get_ctldata(drv_data->master->cur_msg->spi);
u32 sccr1_reg;
sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1;
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
sccr1_reg &= ~QUARK_X1000_SSCR1_RFT;
break;
case CE4100_SSP:
sccr1_reg &= ~CE4100_SSCR1_RFT;
break;
default:
sccr1_reg &= ~SSCR1_RFT;
break;
}
sccr1_reg |= chip->threshold;
pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
}
static void int_error_stop(struct driver_data *drv_data, const char* msg)
{
/* Stop and reset SSP */
write_SSSR_CS(drv_data, drv_data->clear_sr);
reset_sccr1(drv_data);
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, 0);
pxa2xx_spi_flush(drv_data);
pxa2xx_spi_write(drv_data, SSCR0,
pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
dev_err(&drv_data->pdev->dev, "%s\n", msg);
drv_data->master->cur_msg->status = -EIO;
spi_finalize_current_transfer(drv_data->master);
}
static void int_transfer_complete(struct driver_data *drv_data)
{
/* Clear and disable interrupts */
write_SSSR_CS(drv_data, drv_data->clear_sr);
reset_sccr1(drv_data);
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, 0);
spi_finalize_current_transfer(drv_data->master);
}
static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
{
u32 irq_mask = (pxa2xx_spi_read(drv_data, SSCR1) & SSCR1_TIE) ?
drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
u32 irq_status = pxa2xx_spi_read(drv_data, SSSR) & irq_mask;
if (irq_status & SSSR_ROR) {
int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
return IRQ_HANDLED;
}
if (irq_status & SSSR_TINT) {
pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT);
if (drv_data->read(drv_data)) {
int_transfer_complete(drv_data);
return IRQ_HANDLED;
}
}
/* Drain rx fifo, Fill tx fifo and prevent overruns */
do {
if (drv_data->read(drv_data)) {
int_transfer_complete(drv_data);
return IRQ_HANDLED;
}
} while (drv_data->write(drv_data));
if (drv_data->read(drv_data)) {
int_transfer_complete(drv_data);
return IRQ_HANDLED;
}
if (drv_data->tx == drv_data->tx_end) {
u32 bytes_left;
u32 sccr1_reg;
sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
sccr1_reg &= ~SSCR1_TIE;
/*
* PXA25x_SSP has no timeout, set up rx threshould for the
* remaining RX bytes.
*/
if (pxa25x_ssp_comp(drv_data)) {
u32 rx_thre;
pxa2xx_spi_clear_rx_thre(drv_data, &sccr1_reg);
bytes_left = drv_data->rx_end - drv_data->rx;
switch (drv_data->n_bytes) {
case 4:
bytes_left >>= 2;
break;
case 2:
bytes_left >>= 1;
break;
}
rx_thre = pxa2xx_spi_get_rx_default_thre(drv_data);
if (rx_thre > bytes_left)
rx_thre = bytes_left;
pxa2xx_spi_set_rx_thre(drv_data, &sccr1_reg, rx_thre);
}
pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
}
/* We did something */
return IRQ_HANDLED;
}
static void handle_bad_msg(struct driver_data *drv_data)
{
pxa2xx_spi_write(drv_data, SSCR0,
pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
pxa2xx_spi_write(drv_data, SSCR1,
pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1);
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, 0);
write_SSSR_CS(drv_data, drv_data->clear_sr);
dev_err(&drv_data->pdev->dev,
"bad message state in interrupt handler\n");
}
static irqreturn_t ssp_int(int irq, void *dev_id)
{
struct driver_data *drv_data = dev_id;
u32 sccr1_reg;
u32 mask = drv_data->mask_sr;
u32 status;
/*
* The IRQ might be shared with other peripherals so we must first
* check that are we RPM suspended or not. If we are we assume that
* the IRQ was not for us (we shouldn't be RPM suspended when the
* interrupt is enabled).
*/
if (pm_runtime_suspended(&drv_data->pdev->dev))
return IRQ_NONE;
/*
* If the device is not yet in RPM suspended state and we get an
* interrupt that is meant for another device, check if status bits
* are all set to one. That means that the device is already
* powered off.
*/
status = pxa2xx_spi_read(drv_data, SSSR);
if (status == ~0)
return IRQ_NONE;
sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
/* Ignore possible writes if we don't need to write */
if (!(sccr1_reg & SSCR1_TIE))
mask &= ~SSSR_TFS;
/* Ignore RX timeout interrupt if it is disabled */
if (!(sccr1_reg & SSCR1_TINTE))
mask &= ~SSSR_TINT;
if (!(status & mask))
return IRQ_NONE;
pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg & ~drv_data->int_cr1);
pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
if (!drv_data->master->cur_msg) {
handle_bad_msg(drv_data);
/* Never fail */
return IRQ_HANDLED;
}
return drv_data->transfer_handler(drv_data);
}
/*
* The Quark SPI has an additional 24 bit register (DDS_CLK_RATE) to multiply
* input frequency by fractions of 2^24. It also has a divider by 5.
*
* There are formulas to get baud rate value for given input frequency and
* divider parameters, such as DDS_CLK_RATE and SCR:
*
* Fsys = 200MHz
*
* Fssp = Fsys * DDS_CLK_RATE / 2^24 (1)
* Baud rate = Fsclk = Fssp / (2 * (SCR + 1)) (2)
*
* DDS_CLK_RATE either 2^n or 2^n / 5.
* SCR is in range 0 .. 255
*
* Divisor = 5^i * 2^j * 2 * k
* i = [0, 1] i = 1 iff j = 0 or j > 3
* j = [0, 23] j = 0 iff i = 1
* k = [1, 256]
* Special case: j = 0, i = 1: Divisor = 2 / 5
*
* Accordingly to the specification the recommended values for DDS_CLK_RATE
* are:
* Case 1: 2^n, n = [0, 23]
* Case 2: 2^24 * 2 / 5 (0x666666)
* Case 3: less than or equal to 2^24 / 5 / 16 (0x33333)
*
* In all cases the lowest possible value is better.
*
* The function calculates parameters for all cases and chooses the one closest
* to the asked baud rate.
*/
static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
{
unsigned long xtal = 200000000;
unsigned long fref = xtal / 2; /* mandatory division by 2,
see (2) */
/* case 3 */
unsigned long fref1 = fref / 2; /* case 1 */
unsigned long fref2 = fref * 2 / 5; /* case 2 */
unsigned long scale;
unsigned long q, q1, q2;
long r, r1, r2;
u32 mul;
/* Case 1 */
/* Set initial value for DDS_CLK_RATE */
mul = (1 << 24) >> 1;
/* Calculate initial quot */
q1 = DIV_ROUND_UP(fref1, rate);
/* Scale q1 if it's too big */
if (q1 > 256) {
/* Scale q1 to range [1, 512] */
scale = fls_long(q1 - 1);
if (scale > 9) {
q1 >>= scale - 9;
mul >>= scale - 9;
}
/* Round the result if we have a remainder */
q1 += q1 & 1;
}
/* Decrease DDS_CLK_RATE as much as we can without loss in precision */
scale = __ffs(q1);
q1 >>= scale;
mul >>= scale;
/* Get the remainder */
r1 = abs(fref1 / (1 << (24 - fls_long(mul))) / q1 - rate);
/* Case 2 */
q2 = DIV_ROUND_UP(fref2, rate);
r2 = abs(fref2 / q2 - rate);
/*
* Choose the best between two: less remainder we have the better. We
* can't go case 2 if q2 is greater than 256 since SCR register can
* hold only values 0 .. 255.
*/
if (r2 >= r1 || q2 > 256) {
/* case 1 is better */
r = r1;
q = q1;
} else {
/* case 2 is better */
r = r2;
q = q2;
mul = (1 << 24) * 2 / 5;
}
/* Check case 3 only if the divisor is big enough */
if (fref / rate >= 80) {
u64 fssp;
u32 m;
/* Calculate initial quot */
q1 = DIV_ROUND_UP(fref, rate);
m = (1 << 24) / q1;
/* Get the remainder */
fssp = (u64)fref * m;
do_div(fssp, 1 << 24);
r1 = abs(fssp - rate);
/* Choose this one if it suits better */
if (r1 < r) {
/* case 3 is better */
q = 1;
mul = m;
}
}
*dds = mul;
return q - 1;
}
static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
{
unsigned long ssp_clk = drv_data->master->max_speed_hz;
const struct ssp_device *ssp = drv_data->ssp;
rate = min_t(int, ssp_clk, rate);
if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
return (ssp_clk / (2 * rate) - 1) & 0xff;
else
return (ssp_clk / rate - 1) & 0xfff;
}
static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data,
int rate)
{
struct chip_data *chip =
spi_get_ctldata(drv_data->master->cur_msg->spi);
unsigned int clk_div;
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
clk_div = quark_x1000_get_clk_div(rate, &chip->dds_rate);
break;
default:
clk_div = ssp_get_clk_div(drv_data, rate);
break;
}
return clk_div << 8;
}
static bool pxa2xx_spi_can_dma(struct spi_controller *master,
struct spi_device *spi,
struct spi_transfer *xfer)
{
struct chip_data *chip = spi_get_ctldata(spi);
return chip->enable_dma &&
xfer->len <= MAX_DMA_LEN &&
xfer->len >= chip->dma_burst_size;
}
static int pxa2xx_spi_transfer_one(struct spi_controller *master,
struct spi_device *spi,
struct spi_transfer *transfer)
{
struct driver_data *drv_data = spi_controller_get_devdata(master);
struct spi_message *message = master->cur_msg;
struct chip_data *chip = spi_get_ctldata(message->spi);
u32 dma_thresh = chip->dma_threshold;
u32 dma_burst = chip->dma_burst_size;
u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data);
u32 clk_div;
u8 bits;
u32 speed;
u32 cr0;
u32 cr1;
int err;
int dma_mapped;
/* Check if we can DMA this transfer */
if (transfer->len > MAX_DMA_LEN && chip->enable_dma) {
/* reject already-mapped transfers; PIO won't always work */
if (message->is_dma_mapped
|| transfer->rx_dma || transfer->tx_dma) {
dev_err(&drv_data->pdev->dev,
"Mapped transfer length of %u is greater than %d\n",
transfer->len, MAX_DMA_LEN);
return -EINVAL;
}
/* warn ... we force this to PIO mode */
dev_warn_ratelimited(&message->spi->dev,
"DMA disabled for transfer length %ld greater than %d\n",
(long)transfer->len, MAX_DMA_LEN);
}
/* Setup the transfer state based on the type of transfer */
if (pxa2xx_spi_flush(drv_data) == 0) {
dev_err(&drv_data->pdev->dev, "Flush failed\n");
return -EIO;
}
drv_data->n_bytes = chip->n_bytes;
drv_data->tx = (void *)transfer->tx_buf;
drv_data->tx_end = drv_data->tx + transfer->len;
drv_data->rx = transfer->rx_buf;
drv_data->rx_end = drv_data->rx + transfer->len;
drv_data->write = drv_data->tx ? chip->write : null_writer;
drv_data->read = drv_data->rx ? chip->read : null_reader;
/* Change speed and bit per word on a per transfer */
bits = transfer->bits_per_word;
speed = transfer->speed_hz;
clk_div = pxa2xx_ssp_get_clk_div(drv_data, speed);
if (bits <= 8) {
drv_data->n_bytes = 1;
drv_data->read = drv_data->read != null_reader ?
u8_reader : null_reader;
drv_data->write = drv_data->write != null_writer ?
u8_writer : null_writer;
} else if (bits <= 16) {
drv_data->n_bytes = 2;
drv_data->read = drv_data->read != null_reader ?
u16_reader : null_reader;
drv_data->write = drv_data->write != null_writer ?
u16_writer : null_writer;
} else if (bits <= 32) {
drv_data->n_bytes = 4;
drv_data->read = drv_data->read != null_reader ?
u32_reader : null_reader;
drv_data->write = drv_data->write != null_writer ?
u32_writer : null_writer;
}
/*
* if bits/word is changed in dma mode, then must check the
* thresholds and burst also
*/
if (chip->enable_dma) {
if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
message->spi,
bits, &dma_burst,
&dma_thresh))
dev_warn_ratelimited(&message->spi->dev,
"DMA burst size reduced to match bits_per_word\n");
}
dma_mapped = master->can_dma &&
master->can_dma(master, message->spi, transfer) &&
master->cur_msg_mapped;
if (dma_mapped) {
/* Ensure we have the correct interrupt handler */
drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
err = pxa2xx_spi_dma_prepare(drv_data, transfer);
if (err)
return err;
/* Clear status and start DMA engine */
cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
pxa2xx_spi_write(drv_data, SSSR, drv_data->clear_sr);
pxa2xx_spi_dma_start(drv_data);
} else {
/* Ensure we have the correct interrupt handler */
drv_data->transfer_handler = interrupt_transfer;
/* Clear status */
cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
write_SSSR_CS(drv_data, drv_data->clear_sr);
}
/* NOTE: PXA25x_SSP _could_ use external clocking ... */
cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits);
if (!pxa25x_ssp_comp(drv_data))
dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
master->max_speed_hz
/ (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)),
dma_mapped ? "DMA" : "PIO");
else
dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
master->max_speed_hz / 2
/ (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)),
dma_mapped ? "DMA" : "PIO");
if (is_lpss_ssp(drv_data)) {
if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff)
!= chip->lpss_rx_threshold)
pxa2xx_spi_write(drv_data, SSIRF,
chip->lpss_rx_threshold);
if ((pxa2xx_spi_read(drv_data, SSITF) & 0xffff)
!= chip->lpss_tx_threshold)
pxa2xx_spi_write(drv_data, SSITF,
chip->lpss_tx_threshold);
}
if (is_quark_x1000_ssp(drv_data) &&
(pxa2xx_spi_read(drv_data, DDS_RATE) != chip->dds_rate))
pxa2xx_spi_write(drv_data, DDS_RATE, chip->dds_rate);
/* see if we need to reload the config registers */
if ((pxa2xx_spi_read(drv_data, SSCR0) != cr0)
|| (pxa2xx_spi_read(drv_data, SSCR1) & change_mask)
!= (cr1 & change_mask)) {
/* stop the SSP, and update the other bits */
pxa2xx_spi_write(drv_data, SSCR0, cr0 & ~SSCR0_SSE);
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
/* first set CR1 without interrupt and service enables */
pxa2xx_spi_write(drv_data, SSCR1, cr1 & change_mask);
/* restart the SSP */
pxa2xx_spi_write(drv_data, SSCR0, cr0);
} else {
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
}
/*
* Release the data by enabling service requests and interrupts,
* without changing any mode bits
*/
pxa2xx_spi_write(drv_data, SSCR1, cr1);
return 1;
}
static void pxa2xx_spi_handle_err(struct spi_controller *master,
struct spi_message *msg)
{
struct driver_data *drv_data = spi_controller_get_devdata(master);
/* Disable the SSP */
pxa2xx_spi_write(drv_data, SSCR0,
pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
/* Clear and disable interrupts and service requests */
write_SSSR_CS(drv_data, drv_data->clear_sr);
pxa2xx_spi_write(drv_data, SSCR1,
pxa2xx_spi_read(drv_data, SSCR1)
& ~(drv_data->int_cr1 | drv_data->dma_cr1));
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, 0);
/*
* Stop the DMA if running. Note DMA callback handler may have unset
* the dma_running already, which is fine as stopping is not needed
* then but we shouldn't rely this flag for anything else than
* stopping. For instance to differentiate between PIO and DMA
* transfers.
*/
if (atomic_read(&drv_data->dma_running))
pxa2xx_spi_dma_stop(drv_data);
}
static int pxa2xx_spi_unprepare_transfer(struct spi_controller *master)
{
struct driver_data *drv_data = spi_controller_get_devdata(master);
/* Disable the SSP now */
pxa2xx_spi_write(drv_data, SSCR0,
pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
return 0;
}
static int setup_cs(struct spi_device *spi, struct chip_data *chip,
struct pxa2xx_spi_chip *chip_info)
{
struct driver_data *drv_data =
spi_controller_get_devdata(spi->controller);
struct gpio_desc *gpiod;
int err = 0;
if (chip == NULL)
return 0;
if (drv_data->cs_gpiods) {
gpiod = drv_data->cs_gpiods[spi->chip_select];
if (gpiod) {
chip->gpiod_cs = gpiod;
chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
gpiod_set_value(gpiod, chip->gpio_cs_inverted);
}
return 0;
}
if (chip_info == NULL)
return 0;
/* NOTE: setup() can be called multiple times, possibly with
* different chip_info, release previously requested GPIO
*/
if (chip->gpiod_cs) {
gpiod_put(chip->gpiod_cs);
chip->gpiod_cs = NULL;
}
/* If (*cs_control) is provided, ignore GPIO chip select */
if (chip_info->cs_control) {
chip->cs_control = chip_info->cs_control;
return 0;
}
if (gpio_is_valid(chip_info->gpio_cs)) {
err = gpio_request(chip_info->gpio_cs, "SPI_CS");
if (err) {
dev_err(&spi->dev, "failed to request chip select GPIO%d\n",
chip_info->gpio_cs);
return err;
}
gpiod = gpio_to_desc(chip_info->gpio_cs);
chip->gpiod_cs = gpiod;
chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
err = gpiod_direction_output(gpiod, !chip->gpio_cs_inverted);
}
return err;
}
static int setup(struct spi_device *spi)
{
struct pxa2xx_spi_chip *chip_info;
struct chip_data *chip;
const struct lpss_config *config;
struct driver_data *drv_data =
spi_controller_get_devdata(spi->controller);
uint tx_thres, tx_hi_thres, rx_thres;
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
tx_thres = TX_THRESH_QUARK_X1000_DFLT;
tx_hi_thres = 0;
rx_thres = RX_THRESH_QUARK_X1000_DFLT;
break;
case CE4100_SSP:
tx_thres = TX_THRESH_CE4100_DFLT;
tx_hi_thres = 0;
rx_thres = RX_THRESH_CE4100_DFLT;
break;
case LPSS_LPT_SSP:
case LPSS_BYT_SSP:
case LPSS_BSW_SSP:
case LPSS_SPT_SSP:
case LPSS_BXT_SSP:
case LPSS_CNL_SSP:
config = lpss_get_config(drv_data);
tx_thres = config->tx_threshold_lo;
tx_hi_thres = config->tx_threshold_hi;
rx_thres = config->rx_threshold;
break;
default:
tx_thres = TX_THRESH_DFLT;
tx_hi_thres = 0;
rx_thres = RX_THRESH_DFLT;
break;
}
/* Only alloc on first setup */
chip = spi_get_ctldata(spi);
if (!chip) {
chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
if (!chip)
return -ENOMEM;
if (drv_data->ssp_type == CE4100_SSP) {
if (spi->chip_select > 4) {
dev_err(&spi->dev,
"failed setup: cs number must not be > 4.\n");
kfree(chip);
return -EINVAL;
}
chip->frm = spi->chip_select;
}
chip->enable_dma = drv_data->master_info->enable_dma;
chip->timeout = TIMOUT_DFLT;
}
/* protocol drivers may change the chip settings, so...
* if chip_info exists, use it */
chip_info = spi->controller_data;
/* chip_info isn't always needed */
chip->cr1 = 0;
if (chip_info) {
if (chip_info->timeout)
chip->timeout = chip_info->timeout;
if (chip_info->tx_threshold)
tx_thres = chip_info->tx_threshold;
if (chip_info->tx_hi_threshold)
tx_hi_thres = chip_info->tx_hi_threshold;
if (chip_info->rx_threshold)
rx_thres = chip_info->rx_threshold;
chip->dma_threshold = 0;
if (chip_info->enable_loopback)
chip->cr1 = SSCR1_LBM;
}
chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
| SSITF_TxHiThresh(tx_hi_thres);
/* set dma burst and threshold outside of chip_info path so that if
* chip_info goes away after setting chip->enable_dma, the
* burst and threshold can still respond to changes in bits_per_word */
if (chip->enable_dma) {
/* set up legal burst and threshold for dma */
if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
spi->bits_per_word,
&chip->dma_burst_size,
&chip->dma_threshold)) {
dev_warn(&spi->dev,
"in setup: DMA burst size reduced to match bits_per_word\n");
}
}
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres)
& QUARK_X1000_SSCR1_RFT)
| (QUARK_X1000_SSCR1_TxTresh(tx_thres)
& QUARK_X1000_SSCR1_TFT);
break;
case CE4100_SSP:
chip->threshold = (CE4100_SSCR1_RxTresh(rx_thres) & CE4100_SSCR1_RFT) |
(CE4100_SSCR1_TxTresh(tx_thres) & CE4100_SSCR1_TFT);
break;
default:
chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
(SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
break;
}
chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
| (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
if (spi->mode & SPI_LOOP)
chip->cr1 |= SSCR1_LBM;
if (spi->bits_per_word <= 8) {
chip->n_bytes = 1;
chip->read = u8_reader;
chip->write = u8_writer;
} else if (spi->bits_per_word <= 16) {
chip->n_bytes = 2;
chip->read = u16_reader;
chip->write = u16_writer;
} else if (spi->bits_per_word <= 32) {
chip->n_bytes = 4;
chip->read = u32_reader;
chip->write = u32_writer;
}
spi_set_ctldata(spi, chip);
if (drv_data->ssp_type == CE4100_SSP)
return 0;
return setup_cs(spi, chip, chip_info);
}
static void cleanup(struct spi_device *spi)
{
struct chip_data *chip = spi_get_ctldata(spi);
struct driver_data *drv_data =
spi_controller_get_devdata(spi->controller);
if (!chip)
return;
if (drv_data->ssp_type != CE4100_SSP && !drv_data->cs_gpiods &&
chip->gpiod_cs)
gpiod_put(chip->gpiod_cs);
kfree(chip);
}
static const struct acpi_device_id pxa2xx_spi_acpi_match[] = {
{ "INT33C0", LPSS_LPT_SSP },
{ "INT33C1", LPSS_LPT_SSP },
{ "INT3430", LPSS_LPT_SSP },
{ "INT3431", LPSS_LPT_SSP },
{ "80860F0E", LPSS_BYT_SSP },
{ "8086228E", LPSS_BSW_SSP },
{ },
};
MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
/*
* PCI IDs of compound devices that integrate both host controller and private
* integrated DMA engine. Please note these are not used in module
* autoloading and probing in this module but matching the LPSS SSP type.
*/
static const struct pci_device_id pxa2xx_spi_pci_compound_match[] = {
/* SPT-LP */
{ PCI_VDEVICE(INTEL, 0x9d29), LPSS_SPT_SSP },
{ PCI_VDEVICE(INTEL, 0x9d2a), LPSS_SPT_SSP },
/* SPT-H */
{ PCI_VDEVICE(INTEL, 0xa129), LPSS_SPT_SSP },
{ PCI_VDEVICE(INTEL, 0xa12a), LPSS_SPT_SSP },
/* KBL-H */
{ PCI_VDEVICE(INTEL, 0xa2a9), LPSS_SPT_SSP },
{ PCI_VDEVICE(INTEL, 0xa2aa), LPSS_SPT_SSP },
/* BXT A-Step */
{ PCI_VDEVICE(INTEL, 0x0ac2), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x0ac4), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x0ac6), LPSS_BXT_SSP },
/* BXT B-Step */
{ PCI_VDEVICE(INTEL, 0x1ac2), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x1ac4), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x1ac6), LPSS_BXT_SSP },
/* GLK */
{ PCI_VDEVICE(INTEL, 0x31c2), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x31c4), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x31c6), LPSS_BXT_SSP },
/* ICL-LP */
{ PCI_VDEVICE(INTEL, 0x34aa), LPSS_CNL_SSP },
{ PCI_VDEVICE(INTEL, 0x34ab), LPSS_CNL_SSP },
{ PCI_VDEVICE(INTEL, 0x34fb), LPSS_CNL_SSP },
/* APL */
{ PCI_VDEVICE(INTEL, 0x5ac2), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x5ac4), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x5ac6), LPSS_BXT_SSP },
/* CNL-LP */
{ PCI_VDEVICE(INTEL, 0x9daa), LPSS_CNL_SSP },
{ PCI_VDEVICE(INTEL, 0x9dab), LPSS_CNL_SSP },
{ PCI_VDEVICE(INTEL, 0x9dfb), LPSS_CNL_SSP },
/* CNL-H */
{ PCI_VDEVICE(INTEL, 0xa32a), LPSS_CNL_SSP },
{ PCI_VDEVICE(INTEL, 0xa32b), LPSS_CNL_SSP },
{ PCI_VDEVICE(INTEL, 0xa37b), LPSS_CNL_SSP },
{ },
};
static const struct of_device_id pxa2xx_spi_of_match[] = {
{ .compatible = "marvell,mmp2-ssp", .data = (void *)MMP2_SSP },
{},
};
MODULE_DEVICE_TABLE(of, pxa2xx_spi_of_match);
#ifdef CONFIG_ACPI
static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
{
unsigned int devid;
int port_id = -1;
if (adev && adev->pnp.unique_id &&
!kstrtouint(adev->pnp.unique_id, 0, &devid))
port_id = devid;
return port_id;
}
#else /* !CONFIG_ACPI */
static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
{
return -1;
}
#endif /* CONFIG_ACPI */
#ifdef CONFIG_PCI
static bool pxa2xx_spi_idma_filter(struct dma_chan *chan, void *param)
{
struct device *dev = param;
if (dev != chan->device->dev->parent)
return false;
return true;
}
#endif /* CONFIG_PCI */
static struct pxa2xx_spi_master *
pxa2xx_spi_init_pdata(struct platform_device *pdev)
{
struct pxa2xx_spi_master *pdata;
struct acpi_device *adev;
struct ssp_device *ssp;
struct resource *res;
const struct acpi_device_id *adev_id = NULL;
const struct pci_device_id *pcidev_id = NULL;
const struct of_device_id *of_id = NULL;
enum pxa_ssp_type type;
adev = ACPI_COMPANION(&pdev->dev);
if (pdev->dev.of_node)
of_id = of_match_device(pdev->dev.driver->of_match_table,
&pdev->dev);
else if (dev_is_pci(pdev->dev.parent))
pcidev_id = pci_match_id(pxa2xx_spi_pci_compound_match,
to_pci_dev(pdev->dev.parent));
else if (adev)
adev_id = acpi_match_device(pdev->dev.driver->acpi_match_table,
&pdev->dev);
else
return NULL;
if (adev_id)
type = (enum pxa_ssp_type)adev_id->driver_data;
else if (pcidev_id)
type = (enum pxa_ssp_type)pcidev_id->driver_data;
else if (of_id)
type = (enum pxa_ssp_type)of_id->data;
else
return NULL;
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return NULL;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return NULL;
ssp = &pdata->ssp;
ssp->phys_base = res->start;
ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(ssp->mmio_base))
return NULL;
#ifdef CONFIG_PCI
if (pcidev_id) {
pdata->tx_param = pdev->dev.parent;
pdata->rx_param = pdev->dev.parent;
pdata->dma_filter = pxa2xx_spi_idma_filter;
}
#endif
ssp->clk = devm_clk_get(&pdev->dev, NULL);
ssp->irq = platform_get_irq(pdev, 0);
ssp->type = type;
ssp->pdev = pdev;
ssp->port_id = pxa2xx_spi_get_port_id(adev);
pdata->num_chipselect = 1;
pdata->enable_dma = true;
return pdata;
}
static int pxa2xx_spi_fw_translate_cs(struct spi_controller *master,
unsigned int cs)
{
struct driver_data *drv_data = spi_controller_get_devdata(master);
if (has_acpi_companion(&drv_data->pdev->dev)) {
switch (drv_data->ssp_type) {
/*
* For Atoms the ACPI DeviceSelection used by the Windows
* driver starts from 1 instead of 0 so translate it here
* to match what Linux expects.
*/
case LPSS_BYT_SSP:
case LPSS_BSW_SSP:
return cs - 1;
default:
break;
}
}
return cs;
}
static int pxa2xx_spi_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct pxa2xx_spi_master *platform_info;
struct spi_controller *master;
struct driver_data *drv_data;
struct ssp_device *ssp;
const struct lpss_config *config;
int status, count;
u32 tmp;
platform_info = dev_get_platdata(dev);
if (!platform_info) {
platform_info = pxa2xx_spi_init_pdata(pdev);
if (!platform_info) {
dev_err(&pdev->dev, "missing platform data\n");
return -ENODEV;
}
}
ssp = pxa_ssp_request(pdev->id, pdev->name);
if (!ssp)
ssp = &platform_info->ssp;
if (!ssp->mmio_base) {
dev_err(&pdev->dev, "failed to get ssp\n");
return -ENODEV;
}
master = spi_alloc_master(dev, sizeof(struct driver_data));
if (!master) {
dev_err(&pdev->dev, "cannot alloc spi_master\n");
pxa_ssp_free(ssp);
return -ENOMEM;
}
drv_data = spi_controller_get_devdata(master);
drv_data->master = master;
drv_data->master_info = platform_info;
drv_data->pdev = pdev;
drv_data->ssp = ssp;
master->dev.of_node = pdev->dev.of_node;
/* the spi->mode bits understood by this driver: */
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
master->bus_num = ssp->port_id;
master->dma_alignment = DMA_ALIGNMENT;
master->cleanup = cleanup;
master->setup = setup;
master->set_cs = pxa2xx_spi_set_cs;
master->transfer_one = pxa2xx_spi_transfer_one;
master->handle_err = pxa2xx_spi_handle_err;
master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
master->fw_translate_cs = pxa2xx_spi_fw_translate_cs;
master->auto_runtime_pm = true;
master->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
drv_data->ssp_type = ssp->type;
drv_data->ioaddr = ssp->mmio_base;
drv_data->ssdr_physical = ssp->phys_base + SSDR;
if (pxa25x_ssp_comp(drv_data)) {
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
break;
default:
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
break;
}
drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
drv_data->dma_cr1 = 0;
drv_data->clear_sr = SSSR_ROR;
drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
} else {
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
drv_data->dma_cr1 = DEFAULT_DMA_CR1;
drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
}
status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
drv_data);
if (status < 0) {
dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
goto out_error_master_alloc;
}
/* Setup DMA if requested */
if (platform_info->enable_dma) {
status = pxa2xx_spi_dma_setup(drv_data);
if (status) {
dev_dbg(dev, "no DMA channels available, using PIO\n");
platform_info->enable_dma = false;
} else {
master->can_dma = pxa2xx_spi_can_dma;
}
}
/* Enable SOC clock */
status = clk_prepare_enable(ssp->clk);
if (status)
goto out_error_dma_irq_alloc;
master->max_speed_hz = clk_get_rate(ssp->clk);
/* Load default SSP configuration */
pxa2xx_spi_write(drv_data, SSCR0, 0);
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
tmp = QUARK_X1000_SSCR1_RxTresh(RX_THRESH_QUARK_X1000_DFLT) |
QUARK_X1000_SSCR1_TxTresh(TX_THRESH_QUARK_X1000_DFLT);
pxa2xx_spi_write(drv_data, SSCR1, tmp);
/* using the Motorola SPI protocol and use 8 bit frame */
tmp = QUARK_X1000_SSCR0_Motorola | QUARK_X1000_SSCR0_DataSize(8);
pxa2xx_spi_write(drv_data, SSCR0, tmp);
break;
case CE4100_SSP:
tmp = CE4100_SSCR1_RxTresh(RX_THRESH_CE4100_DFLT) |
CE4100_SSCR1_TxTresh(TX_THRESH_CE4100_DFLT);
pxa2xx_spi_write(drv_data, SSCR1, tmp);
tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8);
pxa2xx_spi_write(drv_data, SSCR0, tmp);
break;
default:
tmp = SSCR1_RxTresh(RX_THRESH_DFLT) |
SSCR1_TxTresh(TX_THRESH_DFLT);
pxa2xx_spi_write(drv_data, SSCR1, tmp);
tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8);
pxa2xx_spi_write(drv_data, SSCR0, tmp);
break;
}
if (!pxa25x_ssp_comp(drv_data))
pxa2xx_spi_write(drv_data, SSTO, 0);
if (!is_quark_x1000_ssp(drv_data))
pxa2xx_spi_write(drv_data, SSPSP, 0);
if (is_lpss_ssp(drv_data)) {
lpss_ssp_setup(drv_data);
config = lpss_get_config(drv_data);
if (config->reg_capabilities >= 0) {
tmp = __lpss_ssp_read_priv(drv_data,
config->reg_capabilities);
tmp &= LPSS_CAPS_CS_EN_MASK;
tmp >>= LPSS_CAPS_CS_EN_SHIFT;
platform_info->num_chipselect = ffz(tmp);
} else if (config->cs_num) {
platform_info->num_chipselect = config->cs_num;
}
}
master->num_chipselect = platform_info->num_chipselect;
count = gpiod_count(&pdev->dev, "cs");
if (count > 0) {
int i;
master->num_chipselect = max_t(int, count,
master->num_chipselect);
drv_data->cs_gpiods = devm_kcalloc(&pdev->dev,
master->num_chipselect, sizeof(struct gpio_desc *),
GFP_KERNEL);
if (!drv_data->cs_gpiods) {
status = -ENOMEM;
goto out_error_clock_enabled;
}
for (i = 0; i < master->num_chipselect; i++) {
struct gpio_desc *gpiod;
gpiod = devm_gpiod_get_index(dev, "cs", i, GPIOD_ASIS);
if (IS_ERR(gpiod)) {
/* Means use native chip select */
if (PTR_ERR(gpiod) == -ENOENT)
continue;
status = (int)PTR_ERR(gpiod);
goto out_error_clock_enabled;
} else {
drv_data->cs_gpiods[i] = gpiod;
}
}
}
pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
/* Register with the SPI framework */
platform_set_drvdata(pdev, drv_data);
status = devm_spi_register_controller(&pdev->dev, master);
if (status != 0) {
dev_err(&pdev->dev, "problem registering spi master\n");
goto out_error_clock_enabled;
}
return status;
out_error_clock_enabled:
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_disable(&pdev->dev);
clk_disable_unprepare(ssp->clk);
out_error_dma_irq_alloc:
pxa2xx_spi_dma_release(drv_data);
free_irq(ssp->irq, drv_data);
out_error_master_alloc:
spi_controller_put(master);
pxa_ssp_free(ssp);
return status;
}
static int pxa2xx_spi_remove(struct platform_device *pdev)
{
struct driver_data *drv_data = platform_get_drvdata(pdev);
struct ssp_device *ssp;
if (!drv_data)
return 0;
ssp = drv_data->ssp;
pm_runtime_get_sync(&pdev->dev);
/* Disable the SSP at the peripheral and SOC level */
pxa2xx_spi_write(drv_data, SSCR0, 0);
clk_disable_unprepare(ssp->clk);
/* Release DMA */
if (drv_data->master_info->enable_dma)
pxa2xx_spi_dma_release(drv_data);
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_disable(&pdev->dev);
/* Release IRQ */
free_irq(ssp->irq, drv_data);
/* Release SSP */
pxa_ssp_free(ssp);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int pxa2xx_spi_suspend(struct device *dev)
{
struct driver_data *drv_data = dev_get_drvdata(dev);
struct ssp_device *ssp = drv_data->ssp;
int status;
status = spi_controller_suspend(drv_data->master);
if (status != 0)
return status;
pxa2xx_spi_write(drv_data, SSCR0, 0);
if (!pm_runtime_suspended(dev))
clk_disable_unprepare(ssp->clk);
return 0;
}
static int pxa2xx_spi_resume(struct device *dev)
{
struct driver_data *drv_data = dev_get_drvdata(dev);
struct ssp_device *ssp = drv_data->ssp;
int status;
/* Enable the SSP clock */
if (!pm_runtime_suspended(dev)) {
status = clk_prepare_enable(ssp->clk);
if (status)
return status;
}
/* Restore LPSS private register bits */
if (is_lpss_ssp(drv_data))
lpss_ssp_setup(drv_data);
/* Start the queue running */
return spi_controller_resume(drv_data->master);
}
#endif
#ifdef CONFIG_PM
static int pxa2xx_spi_runtime_suspend(struct device *dev)
{
struct driver_data *drv_data = dev_get_drvdata(dev);
clk_disable_unprepare(drv_data->ssp->clk);
return 0;
}
static int pxa2xx_spi_runtime_resume(struct device *dev)
{
struct driver_data *drv_data = dev_get_drvdata(dev);
int status;
status = clk_prepare_enable(drv_data->ssp->clk);
return status;
}
#endif
static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
pxa2xx_spi_runtime_resume, NULL)
};
static struct platform_driver driver = {
.driver = {
.name = "pxa2xx-spi",
.pm = &pxa2xx_spi_pm_ops,
.acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
.of_match_table = of_match_ptr(pxa2xx_spi_of_match),
},
.probe = pxa2xx_spi_probe,
.remove = pxa2xx_spi_remove,
};
static int __init pxa2xx_spi_init(void)
{
return platform_driver_register(&driver);
}
subsys_initcall(pxa2xx_spi_init);
static void __exit pxa2xx_spi_exit(void)
{
platform_driver_unregister(&driver);
}
module_exit(pxa2xx_spi_exit);
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