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Merge tag 'spi-fix-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/ke…
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…rnel/git/broonie/spi

Pull spi fixes from Mark Brown:
 "A bunch of fixes that came in for SPI during the merge window.

  Some from ST and others for their controller, one from Lukas for a
  race between device addition and controller unregistration and one
  from fix from Geert for the DT bindings which unbreaks validation"

* tag 'spi-fix-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  dt-bindings: lpspi: Add missing boolean type for fsl,spi-only-use-cs1-sel
  spi: stm32: always perform registers configuration prior to transfer
  spi: stm32: fixes suspend/resume management
  spi: stm32: fix stm32_spi_prepare_mbr in case of odd clk_rate
  spi: stm32: fix fifo threshold level in case of short transfer
  spi: stm32h7: fix race condition at end of transfer
  spi: stm32: clear only asserted irq flags on interrupt
  spi: Prevent adding devices below an unregistering controller
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torvalds committed Aug 18, 2020
2 parents 9899b58 + 8cb61d6 commit 18445bf
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Showing 4 changed files with 86 additions and 39 deletions.
1 change: 1 addition & 0 deletions Documentation/devicetree/bindings/spi/spi-fsl-lpspi.yaml
Original file line number Diff line number Diff line change
Expand Up @@ -39,6 +39,7 @@ properties:
spi common code does not support use of CS signals discontinuously.
i.MX8DXL-EVK board only uses CS1 without using CS0. Therefore, add
this property to re-config the chipselect value in the LPSPI driver.
type: boolean

required:
- compatible
Expand Down
3 changes: 3 additions & 0 deletions drivers/spi/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -1017,4 +1017,7 @@ config SPI_SLAVE_SYSTEM_CONTROL

endif # SPI_SLAVE

config SPI_DYNAMIC
def_bool ACPI || OF_DYNAMIC || SPI_SLAVE

endif # SPI
100 changes: 62 additions & 38 deletions drivers/spi/spi-stm32.c
Original file line number Diff line number Diff line change
Expand Up @@ -13,6 +13,7 @@
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>
#include <linux/spi/spi.h>
Expand Down Expand Up @@ -441,7 +442,8 @@ static int stm32_spi_prepare_mbr(struct stm32_spi *spi, u32 speed_hz,
{
u32 div, mbrdiv;

div = DIV_ROUND_UP(spi->clk_rate, speed_hz);
/* Ensure spi->clk_rate is even */
div = DIV_ROUND_UP(spi->clk_rate & ~0x1, speed_hz);

/*
* SPI framework set xfer->speed_hz to master->max_speed_hz if
Expand All @@ -467,27 +469,37 @@ static int stm32_spi_prepare_mbr(struct stm32_spi *spi, u32 speed_hz,
/**
* stm32h7_spi_prepare_fthlv - Determine FIFO threshold level
* @spi: pointer to the spi controller data structure
* @xfer_len: length of the message to be transferred
*/
static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi)
static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi, u32 xfer_len)
{
u32 fthlv, half_fifo;
u32 fthlv, half_fifo, packet;

/* data packet should not exceed 1/2 of fifo space */
half_fifo = (spi->fifo_size / 2);

/* data_packet should not exceed transfer length */
if (half_fifo > xfer_len)
packet = xfer_len;
else
packet = half_fifo;

if (spi->cur_bpw <= 8)
fthlv = half_fifo;
fthlv = packet;
else if (spi->cur_bpw <= 16)
fthlv = half_fifo / 2;
fthlv = packet / 2;
else
fthlv = half_fifo / 4;
fthlv = packet / 4;

/* align packet size with data registers access */
if (spi->cur_bpw > 8)
fthlv -= (fthlv % 2); /* multiple of 2 */
else
fthlv -= (fthlv % 4); /* multiple of 4 */

if (!fthlv)
fthlv = 1;

return fthlv;
}

Expand Down Expand Up @@ -966,13 +978,13 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0)))
stm32h7_spi_read_rxfifo(spi, false);

writel_relaxed(mask, spi->base + STM32H7_SPI_IFCR);
writel_relaxed(sr & mask, spi->base + STM32H7_SPI_IFCR);

spin_unlock_irqrestore(&spi->lock, flags);

if (end) {
spi_finalize_current_transfer(master);
stm32h7_spi_disable(spi);
spi_finalize_current_transfer(master);
}

return IRQ_HANDLED;
Expand Down Expand Up @@ -1393,7 +1405,7 @@ static void stm32h7_spi_set_bpw(struct stm32_spi *spi)
cfg1_setb |= (bpw << STM32H7_SPI_CFG1_DSIZE_SHIFT) &
STM32H7_SPI_CFG1_DSIZE;

spi->cur_fthlv = stm32h7_spi_prepare_fthlv(spi);
spi->cur_fthlv = stm32h7_spi_prepare_fthlv(spi, spi->cur_xferlen);
fthlv = spi->cur_fthlv - 1;

cfg1_clrb |= STM32H7_SPI_CFG1_FTHLV;
Expand Down Expand Up @@ -1585,39 +1597,33 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,
unsigned long flags;
unsigned int comm_type;
int nb_words, ret = 0;
int mbr;

spin_lock_irqsave(&spi->lock, flags);

if (spi->cur_bpw != transfer->bits_per_word) {
spi->cur_bpw = transfer->bits_per_word;
spi->cfg->set_bpw(spi);
}

if (spi->cur_speed != transfer->speed_hz) {
int mbr;
spi->cur_xferlen = transfer->len;

/* Update spi->cur_speed with real clock speed */
mbr = stm32_spi_prepare_mbr(spi, transfer->speed_hz,
spi->cfg->baud_rate_div_min,
spi->cfg->baud_rate_div_max);
if (mbr < 0) {
ret = mbr;
goto out;
}
spi->cur_bpw = transfer->bits_per_word;
spi->cfg->set_bpw(spi);

transfer->speed_hz = spi->cur_speed;
stm32_spi_set_mbr(spi, mbr);
/* Update spi->cur_speed with real clock speed */
mbr = stm32_spi_prepare_mbr(spi, transfer->speed_hz,
spi->cfg->baud_rate_div_min,
spi->cfg->baud_rate_div_max);
if (mbr < 0) {
ret = mbr;
goto out;
}

transfer->speed_hz = spi->cur_speed;
stm32_spi_set_mbr(spi, mbr);

comm_type = stm32_spi_communication_type(spi_dev, transfer);
if (spi->cur_comm != comm_type) {
ret = spi->cfg->set_mode(spi, comm_type);
ret = spi->cfg->set_mode(spi, comm_type);
if (ret < 0)
goto out;

if (ret < 0)
goto out;

spi->cur_comm = comm_type;
}
spi->cur_comm = comm_type;

if (spi->cfg->set_data_idleness)
spi->cfg->set_data_idleness(spi, transfer->len);
Expand All @@ -1635,8 +1641,6 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,
goto out;
}

spi->cur_xferlen = transfer->len;

dev_dbg(spi->dev, "transfer communication mode set to %d\n",
spi->cur_comm);
dev_dbg(spi->dev,
Expand Down Expand Up @@ -1996,6 +2000,8 @@ static int stm32_spi_remove(struct platform_device *pdev)

pm_runtime_disable(&pdev->dev);

pinctrl_pm_select_sleep_state(&pdev->dev);

return 0;
}

Expand All @@ -2007,13 +2013,18 @@ static int stm32_spi_runtime_suspend(struct device *dev)

clk_disable_unprepare(spi->clk);

return 0;
return pinctrl_pm_select_sleep_state(dev);
}

static int stm32_spi_runtime_resume(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct stm32_spi *spi = spi_master_get_devdata(master);
int ret;

ret = pinctrl_pm_select_default_state(dev);
if (ret)
return ret;

return clk_prepare_enable(spi->clk);
}
Expand Down Expand Up @@ -2043,10 +2054,23 @@ static int stm32_spi_resume(struct device *dev)
return ret;

ret = spi_master_resume(master);
if (ret)
if (ret) {
clk_disable_unprepare(spi->clk);
return ret;
}

return ret;
ret = pm_runtime_get_sync(dev);
if (ret) {
dev_err(dev, "Unable to power device:%d\n", ret);
return ret;
}

spi->cfg->config(spi);

pm_runtime_mark_last_busy(dev);
pm_runtime_put_autosuspend(dev);

return 0;
}
#endif

Expand Down
21 changes: 20 additions & 1 deletion drivers/spi/spi.c
Original file line number Diff line number Diff line change
Expand Up @@ -475,6 +475,12 @@ static LIST_HEAD(spi_controller_list);
*/
static DEFINE_MUTEX(board_lock);

/*
* Prevents addition of devices with same chip select and
* addition of devices below an unregistering controller.
*/
static DEFINE_MUTEX(spi_add_lock);

/**
* spi_alloc_device - Allocate a new SPI device
* @ctlr: Controller to which device is connected
Expand Down Expand Up @@ -554,7 +560,6 @@ static int spi_dev_check(struct device *dev, void *data)
*/
int spi_add_device(struct spi_device *spi)
{
static DEFINE_MUTEX(spi_add_lock);
struct spi_controller *ctlr = spi->controller;
struct device *dev = ctlr->dev.parent;
int status;
Expand Down Expand Up @@ -582,6 +587,13 @@ int spi_add_device(struct spi_device *spi)
goto done;
}

/* Controller may unregister concurrently */
if (IS_ENABLED(CONFIG_SPI_DYNAMIC) &&
!device_is_registered(&ctlr->dev)) {
status = -ENODEV;
goto done;
}

/* Descriptors take precedence */
if (ctlr->cs_gpiods)
spi->cs_gpiod = ctlr->cs_gpiods[spi->chip_select];
Expand Down Expand Up @@ -2795,6 +2807,10 @@ void spi_unregister_controller(struct spi_controller *ctlr)
struct spi_controller *found;
int id = ctlr->bus_num;

/* Prevent addition of new devices, unregister existing ones */
if (IS_ENABLED(CONFIG_SPI_DYNAMIC))
mutex_lock(&spi_add_lock);

device_for_each_child(&ctlr->dev, NULL, __unregister);

/* First make sure that this controller was ever added */
Expand All @@ -2815,6 +2831,9 @@ void spi_unregister_controller(struct spi_controller *ctlr)
if (found == ctlr)
idr_remove(&spi_master_idr, id);
mutex_unlock(&board_lock);

if (IS_ENABLED(CONFIG_SPI_DYNAMIC))
mutex_unlock(&spi_add_lock);
}
EXPORT_SYMBOL_GPL(spi_unregister_controller);

Expand Down

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