summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--Documentation/devicetree/bindings/spi/icpdas-lp8841-spi-rtc.txt54
-rw-r--r--drivers/spi/Kconfig14
-rw-r--r--drivers/spi/Makefile4
-rw-r--r--drivers/spi/spi-lp8841-rtc.c256
-rw-r--r--drivers/spi/spi-pl022.c7
-rw-r--r--drivers/spi/spi-pxa2xx-dma.c8
-rw-r--r--drivers/spi/spi-pxa2xx-pci.c13
-rw-r--r--drivers/spi/spi-pxa2xx.c151
-rw-r--r--drivers/spi/spi-pxa2xx.h37
-rw-r--r--drivers/spi/spi.c336
-rw-r--r--include/linux/pxa2xx_ssp.h1
-rw-r--r--include/linux/spi/spi.h96
12 files changed, 881 insertions, 96 deletions
diff --git a/Documentation/devicetree/bindings/spi/icpdas-lp8841-spi-rtc.txt b/Documentation/devicetree/bindings/spi/icpdas-lp8841-spi-rtc.txt
new file mode 100644
index 000000000000..852b651f3bc5
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/icpdas-lp8841-spi-rtc.txt
@@ -0,0 +1,54 @@
+* ICP DAS LP-8841 SPI Controller for RTC
+
+ICP DAS LP-8841 contains a DS-1302 RTC. RTC is connected to an IO
+memory register, which acts as an SPI master device.
+
+The device uses the standard MicroWire half-duplex transfer timing.
+Master output is set on low clock and sensed by the RTC on the rising
+edge. Master input is set by the RTC on the trailing edge and is sensed
+by the master on low clock.
+
+Required properties:
+
+- #address-cells: should be 1
+
+- #size-cells: should be 0
+
+- compatible: should be "icpdas,lp8841-spi-rtc"
+
+- reg: should provide IO memory address
+
+Requirements to SPI slave nodes:
+
+- There can be only one slave device.
+
+- The spi slave node should claim the following flags which are
+ required by the spi controller.
+
+ - spi-3wire: The master itself has only 3 wire. It cannor work in
+ full duplex mode.
+
+ - spi-cs-high: DS-1302 has active high chip select line. The master
+ doesn't support active low.
+
+ - spi-lsb-first: DS-1302 requires least significant bit first
+ transfers. The master only support this type of bit ordering.
+
+
+Example:
+
+spi@901c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "icpdas,lp8841-spi-rtc";
+ reg = <0x901c 0x1>;
+
+ rtc@0 {
+ compatible = "maxim,ds1302";
+ reg = <0>;
+ spi-max-frequency = <500000>;
+ spi-3wire;
+ spi-lsb-first;
+ spi-cs-high;
+ };
+};
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 77d3202f163d..c2a0404923f9 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -294,6 +294,16 @@ config SPI_LM70_LLP
which interfaces to an LM70 temperature sensor using
a parallel port.
+config SPI_LP8841_RTC
+ tristate "ICP DAS LP-8841 SPI Controller for RTC"
+ depends on MACH_PXA27X_DT || COMPILE_TEST
+ help
+ This driver provides an SPI master device to drive Maxim
+ DS-1302 real time clock.
+
+ Say N here unless you plan to run the kernel on an ICP DAS
+ LP-8x4x industrial computer.
+
config SPI_MPC52xx
tristate "Freescale MPC52xx SPI (non-PSC) controller support"
depends on PPC_MPC52xx
@@ -445,10 +455,6 @@ config SPI_PPC4xx
help
This selects a driver for the PPC4xx SPI Controller.
-config SPI_PXA2XX_DMA
- def_bool y
- depends on SPI_PXA2XX
-
config SPI_PXA2XX
tristate "PXA2xx SSP SPI master"
depends on (ARCH_PXA || PCI || ACPI)
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 7ad880684a85..fbb255c5a608 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -47,6 +47,7 @@ obj-$(CONFIG_SPI_GPIO) += spi-gpio.o
obj-$(CONFIG_SPI_IMG_SPFI) += spi-img-spfi.o
obj-$(CONFIG_SPI_IMX) += spi-imx.o
obj-$(CONFIG_SPI_LM70_LLP) += spi-lm70llp.o
+obj-$(CONFIG_SPI_LP8841_RTC) += spi-lp8841-rtc.o
obj-$(CONFIG_SPI_MESON_SPIFC) += spi-meson-spifc.o
obj-$(CONFIG_SPI_MPC512x_PSC) += spi-mpc512x-psc.o
obj-$(CONFIG_SPI_MPC52xx_PSC) += spi-mpc52xx-psc.o
@@ -63,8 +64,7 @@ obj-$(CONFIG_SPI_TI_QSPI) += spi-ti-qspi.o
obj-$(CONFIG_SPI_ORION) += spi-orion.o
obj-$(CONFIG_SPI_PL022) += spi-pl022.o
obj-$(CONFIG_SPI_PPC4xx) += spi-ppc4xx.o
-spi-pxa2xx-platform-objs := spi-pxa2xx.o
-spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_DMA) += spi-pxa2xx-dma.o
+spi-pxa2xx-platform-objs := spi-pxa2xx.o spi-pxa2xx-dma.o
obj-$(CONFIG_SPI_PXA2XX) += spi-pxa2xx-platform.o
obj-$(CONFIG_SPI_PXA2XX_PCI) += spi-pxa2xx-pci.o
obj-$(CONFIG_SPI_QUP) += spi-qup.o
diff --git a/drivers/spi/spi-lp8841-rtc.c b/drivers/spi/spi-lp8841-rtc.c
new file mode 100644
index 000000000000..faa577d282c0
--- /dev/null
+++ b/drivers/spi/spi-lp8841-rtc.c
@@ -0,0 +1,256 @@
+/*
+ * SPI master driver for ICP DAS LP-8841 RTC
+ *
+ * Copyright (C) 2016 Sergei Ianovich
+ *
+ * based on
+ *
+ * Dallas DS1302 RTC Support
+ * Copyright (C) 2002 David McCullough
+ * Copyright (C) 2003 - 2007 Paul Mundt
+ *
+ * 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/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/spi/spi.h>
+
+#define DRIVER_NAME "spi_lp8841_rtc"
+
+#define SPI_LP8841_RTC_CE 0x01
+#define SPI_LP8841_RTC_CLK 0x02
+#define SPI_LP8841_RTC_nWE 0x04
+#define SPI_LP8841_RTC_MOSI 0x08
+#define SPI_LP8841_RTC_MISO 0x01
+
+/*
+ * REVISIT If there is support for SPI_3WIRE and SPI_LSB_FIRST in SPI
+ * GPIO driver, this SPI driver can be replaced by a simple GPIO driver
+ * providing 3 GPIO pins.
+ */
+
+struct spi_lp8841_rtc {
+ void *iomem;
+ unsigned long state;
+};
+
+static inline void
+setsck(struct spi_lp8841_rtc *data, int is_on)
+{
+ if (is_on)
+ data->state |= SPI_LP8841_RTC_CLK;
+ else
+ data->state &= ~SPI_LP8841_RTC_CLK;
+ writeb(data->state, data->iomem);
+}
+
+static inline void
+setmosi(struct spi_lp8841_rtc *data, int is_on)
+{
+ if (is_on)
+ data->state |= SPI_LP8841_RTC_MOSI;
+ else
+ data->state &= ~SPI_LP8841_RTC_MOSI;
+ writeb(data->state, data->iomem);
+}
+
+static inline int
+getmiso(struct spi_lp8841_rtc *data)
+{
+ return ioread8(data->iomem) & SPI_LP8841_RTC_MISO;
+}
+
+static inline u32
+bitbang_txrx_be_cpha0_lsb(struct spi_lp8841_rtc *data,
+ unsigned usecs, unsigned cpol, unsigned flags,
+ u32 word, u8 bits)
+{
+ /* if (cpol == 0) this is SPI_MODE_0; else this is SPI_MODE_2 */
+
+ u32 shift = 32 - bits;
+ /* clock starts at inactive polarity */
+ for (; likely(bits); bits--) {
+
+ /* setup LSB (to slave) on leading edge */
+ if ((flags & SPI_MASTER_NO_TX) == 0)
+ setmosi(data, (word & 1));
+
+ usleep_range(usecs, usecs + 1); /* T(setup) */
+
+ /* sample LSB (from slave) on trailing edge */
+ word >>= 1;
+ if ((flags & SPI_MASTER_NO_RX) == 0)
+ word |= (getmiso(data) << 31);
+
+ setsck(data, !cpol);
+ usleep_range(usecs, usecs + 1);
+
+ setsck(data, cpol);
+ }
+
+ word >>= shift;
+ return word;
+}
+
+static int
+spi_lp8841_rtc_transfer_one(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct spi_lp8841_rtc *data = spi_master_get_devdata(master);
+ unsigned count = t->len;
+ const u8 *tx = t->tx_buf;
+ u8 *rx = t->rx_buf;
+ u8 word = 0;
+ int ret = 0;
+
+ if (tx) {
+ data->state &= ~SPI_LP8841_RTC_nWE;
+ writeb(data->state, data->iomem);
+ while (likely(count > 0)) {
+ word = *tx++;
+ bitbang_txrx_be_cpha0_lsb(data, 1, 0,
+ SPI_MASTER_NO_RX, word, 8);
+ count--;
+ }
+ } else if (rx) {
+ data->state |= SPI_LP8841_RTC_nWE;
+ writeb(data->state, data->iomem);
+ while (likely(count > 0)) {
+ word = bitbang_txrx_be_cpha0_lsb(data, 1, 0,
+ SPI_MASTER_NO_TX, word, 8);
+ *rx++ = word;
+ count--;
+ }
+ } else {
+ ret = -EINVAL;
+ }
+
+ spi_finalize_current_transfer(master);
+
+ return ret;
+}
+
+static void
+spi_lp8841_rtc_set_cs(struct spi_device *spi, bool enable)
+{
+ struct spi_lp8841_rtc *data = spi_master_get_devdata(spi->master);
+
+ data->state = 0;
+ writeb(data->state, data->iomem);
+ if (enable) {
+ usleep_range(4, 5);
+ data->state |= SPI_LP8841_RTC_CE;
+ writeb(data->state, data->iomem);
+ usleep_range(4, 5);
+ }
+}
+
+static int
+spi_lp8841_rtc_setup(struct spi_device *spi)
+{
+ if ((spi->mode & SPI_CS_HIGH) == 0) {
+ dev_err(&spi->dev, "unsupported active low chip select\n");
+ return -EINVAL;
+ }
+
+ if ((spi->mode & SPI_LSB_FIRST) == 0) {
+ dev_err(&spi->dev, "unsupported MSB first mode\n");
+ return -EINVAL;
+ }
+
+ if ((spi->mode & SPI_3WIRE) == 0) {
+ dev_err(&spi->dev, "unsupported wiring. 3 wires required\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id spi_lp8841_rtc_dt_ids[] = {
+ { .compatible = "icpdas,lp8841-spi-rtc" },
+ { }
+};
+
+MODULE_DEVICE_TABLE(of, spi_lp8841_rtc_dt_ids);
+#endif
+
+static int
+spi_lp8841_rtc_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct spi_master *master;
+ struct spi_lp8841_rtc *data;
+ void *iomem;
+
+ master = spi_alloc_master(&pdev->dev, sizeof(*data));
+ if (!master)
+ return -ENOMEM;
+ platform_set_drvdata(pdev, master);
+
+ master->flags = SPI_MASTER_HALF_DUPLEX;
+ master->mode_bits = SPI_CS_HIGH | SPI_3WIRE | SPI_LSB_FIRST;
+
+ master->bus_num = pdev->id;
+ master->num_chipselect = 1;
+ master->setup = spi_lp8841_rtc_setup;
+ master->set_cs = spi_lp8841_rtc_set_cs;
+ master->transfer_one = spi_lp8841_rtc_transfer_one;
+ master->bits_per_word_mask = SPI_BPW_MASK(8);
+#ifdef CONFIG_OF
+ master->dev.of_node = pdev->dev.of_node;
+#endif
+
+ data = spi_master_get_devdata(master);
+
+ iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ data->iomem = devm_ioremap_resource(&pdev->dev, iomem);
+ ret = PTR_ERR_OR_ZERO(data->iomem);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to get IO address\n");
+ goto err_put_master;
+ }
+
+ /* register with the SPI framework */
+ ret = devm_spi_register_master(&pdev->dev, master);
+ if (ret) {
+ dev_err(&pdev->dev, "cannot register spi master\n");
+ goto err_put_master;
+ }
+
+ return ret;
+
+
+err_put_master:
+ spi_master_put(master);
+
+ return ret;
+}
+
+MODULE_ALIAS("platform:" DRIVER_NAME);
+
+static struct platform_driver spi_lp8841_rtc_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = of_match_ptr(spi_lp8841_rtc_dt_ids),
+ },
+ .probe = spi_lp8841_rtc_probe,
+};
+module_platform_driver(spi_lp8841_rtc_driver);
+
+MODULE_DESCRIPTION("SPI master driver for ICP DAS LP-8841 RTC");
+MODULE_AUTHOR("Sergei Ianovich");
+MODULE_LICENSE("GPL");
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c
index 5e5fd77e2711..f7f7ba17b40e 100644
--- a/drivers/spi/spi-pl022.c
+++ b/drivers/spi/spi-pl022.c
@@ -346,13 +346,6 @@ struct vendor_data {
* @clk: outgoing clock "SPICLK" for the SPI bus
* @master: SPI framework hookup
* @master_info: controller-specific data from machine setup
- * @kworker: thread struct for message pump
- * @kworker_task: pointer to task for message pump kworker thread
- * @pump_messages: work struct for scheduling work to the message pump
- * @queue_lock: spinlock to syncronise access to message queue
- * @queue: message queue
- * @busy: message pump is busy
- * @running: message pump 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
diff --git a/drivers/spi/spi-pxa2xx-dma.c b/drivers/spi/spi-pxa2xx-dma.c
index bd8b369a343c..365fc22c3572 100644
--- a/drivers/spi/spi-pxa2xx-dma.c
+++ b/drivers/spi/spi-pxa2xx-dma.c
@@ -254,8 +254,8 @@ irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data)
if (status & SSSR_ROR) {
dev_err(&drv_data->pdev->dev, "FIFO overrun\n");
- dmaengine_terminate_all(drv_data->rx_chan);
- dmaengine_terminate_all(drv_data->tx_chan);
+ dmaengine_terminate_async(drv_data->rx_chan);
+ dmaengine_terminate_async(drv_data->tx_chan);
pxa2xx_spi_dma_transfer_complete(drv_data, true);
return IRQ_HANDLED;
@@ -331,13 +331,13 @@ int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
void pxa2xx_spi_dma_release(struct driver_data *drv_data)
{
if (drv_data->rx_chan) {
- dmaengine_terminate_all(drv_data->rx_chan);
+ dmaengine_terminate_sync(drv_data->rx_chan);
dma_release_channel(drv_data->rx_chan);
sg_free_table(&drv_data->rx_sgt);
drv_data->rx_chan = NULL;
}
if (drv_data->tx_chan) {
- dmaengine_terminate_all(drv_data->tx_chan);
+ dmaengine_terminate_sync(drv_data->tx_chan);
dma_release_channel(drv_data->tx_chan);
sg_free_table(&drv_data->tx_sgt);
drv_data->tx_chan = NULL;
diff --git a/drivers/spi/spi-pxa2xx-pci.c b/drivers/spi/spi-pxa2xx-pci.c
index d19d7f28aecb..520ed1dd5780 100644
--- a/drivers/spi/spi-pxa2xx-pci.c
+++ b/drivers/spi/spi-pxa2xx-pci.c
@@ -19,6 +19,7 @@ enum {
PORT_BSW1,
PORT_BSW2,
PORT_QUARK_X1000,
+ PORT_LPT,
};
struct pxa_spi_info {
@@ -42,6 +43,9 @@ static struct dw_dma_slave bsw1_rx_param = { .src_id = 7 };
static struct dw_dma_slave bsw2_tx_param = { .dst_id = 8 };
static struct dw_dma_slave bsw2_rx_param = { .src_id = 9 };
+static struct dw_dma_slave lpt_tx_param = { .dst_id = 0 };
+static struct dw_dma_slave lpt_rx_param = { .src_id = 1 };
+
static bool lpss_dma_filter(struct dma_chan *chan, void *param)
{
struct dw_dma_slave *dws = param;
@@ -98,6 +102,14 @@ static struct pxa_spi_info spi_info_configs[] = {
.num_chipselect = 1,
.max_clk_rate = 50000000,
},
+ [PORT_LPT] = {
+ .type = LPSS_LPT_SSP,
+ .port_id = 0,
+ .num_chipselect = 1,
+ .max_clk_rate = 50000000,
+ .tx_param = &lpt_tx_param,
+ .rx_param = &lpt_rx_param,
+ },
};
static int pxa2xx_spi_pci_probe(struct pci_dev *dev,
@@ -202,6 +214,7 @@ static const struct pci_device_id pxa2xx_spi_pci_devices[] = {
{ PCI_VDEVICE(INTEL, 0x228e), PORT_BSW0 },
{ PCI_VDEVICE(INTEL, 0x2290), PORT_BSW1 },
{ PCI_VDEVICE(INTEL, 0x22ac), PORT_BSW2 },
+ { PCI_VDEVICE(INTEL, 0x9ce6), PORT_LPT },
{ },
};
MODULE_DEVICE_TABLE(pci, pxa2xx_spi_pci_devices);
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index ab9914ad8365..85e59a406a4c 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -65,8 +65,6 @@ MODULE_ALIAS("platform:pxa2xx-spi");
#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_CS_CONTROL_CS_SEL_SHIFT 8
-#define LPSS_CS_CONTROL_CS_SEL_MASK (3 << LPSS_CS_CONTROL_CS_SEL_SHIFT)
#define LPSS_CAPS_CS_EN_SHIFT 9
#define LPSS_CAPS_CS_EN_MASK (0xf << LPSS_CAPS_CS_EN_SHIFT)
@@ -82,6 +80,10 @@ struct lpss_config {
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 */
@@ -106,6 +108,19 @@ static const struct lpss_config lpss_platforms[] = {
.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,
@@ -125,6 +140,8 @@ static const struct lpss_config lpss_platforms[] = {
.rx_threshold = 1,
.tx_threshold_lo = 16,
.tx_threshold_hi = 48,
+ .cs_sel_shift = 8,
+ .cs_sel_mask = 3 << 8,
},
};
@@ -139,6 +156,7 @@ 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:
return true;
@@ -288,37 +306,50 @@ static void lpss_ssp_setup(struct driver_data *drv_data)
}
}
+static void lpss_ssp_select_cs(struct driver_data *drv_data,
+ const struct lpss_config *config)
+{
+ u32 value, cs;
+
+ if (!config->cs_sel_mask)
+ return;
+
+ value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
+
+ cs = drv_data->cur_msg->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 driver_data *drv_data, bool enable)
{
const struct lpss_config *config;
- u32 value, cs;
+ u32 value;
config = lpss_get_config(drv_data);
+ if (enable)
+ lpss_ssp_select_cs(drv_data, config);
+
value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
- if (enable) {
- cs = drv_data->cur_msg->spi->chip_select;
- cs <<= LPSS_CS_CONTROL_CS_SEL_SHIFT;
- if (cs != (value & LPSS_CS_CONTROL_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 &= ~LPSS_CS_CONTROL_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));
- }
+ if (enable)
value &= ~LPSS_CS_CONTROL_CS_HIGH;
- } else {
+ else
value |= LPSS_CS_CONTROL_CS_HIGH;
- }
__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
}
@@ -496,6 +527,7 @@ static void giveback(struct driver_data *drv_data)
{
struct spi_transfer* last_transfer;
struct spi_message *msg;
+ unsigned long timeout;
msg = drv_data->cur_msg;
drv_data->cur_msg = NULL;
@@ -508,6 +540,12 @@ static void giveback(struct driver_data *drv_data)
if (last_transfer->delay_usecs)
udelay(last_transfer->delay_usecs);
+ /* 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();
+
/* Drop chip select UNLESS cs_change is true or we are returning
* a message with an error, or next message is for another chip
*/
@@ -572,7 +610,7 @@ static void int_error_stop(struct driver_data *drv_data, const char* msg)
static void int_transfer_complete(struct driver_data *drv_data)
{
- /* Stop SSP */
+ /* Clear and disable interrupts */
write_SSSR_CS(drv_data, drv_data->clear_sr);
reset_sccr1(drv_data);
if (!pxa25x_ssp_comp(drv_data))
@@ -957,8 +995,6 @@ static void pump_transfers(unsigned long data)
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->rx_dma = transfer->rx_dma;
- drv_data->tx_dma = transfer->tx_dma;
drv_data->len = transfer->len;
drv_data->write = drv_data->tx ? chip->write : null_writer;
drv_data->read = drv_data->rx ? chip->read : null_reader;
@@ -1001,19 +1037,6 @@ static void pump_transfers(unsigned long data)
"pump_transfers: DMA burst size reduced to match bits_per_word\n");
}
- /* 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",
- drv_data->master->max_speed_hz
- / (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)),
- chip->enable_dma ? "DMA" : "PIO");
- else
- dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
- drv_data->master->max_speed_hz / 2
- / (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)),
- chip->enable_dma ? "DMA" : "PIO");
-
message->state = RUNNING_STATE;
drv_data->dma_mapped = 0;
@@ -1040,6 +1063,19 @@ static void pump_transfers(unsigned long data)
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",
+ drv_data->master->max_speed_hz
+ / (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)),
+ drv_data->dma_mapped ? "DMA" : "PIO");
+ else
+ dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
+ drv_data->master->max_speed_hz / 2
+ / (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)),
+ drv_data->dma_mapped ? "DMA" : "PIO");
+
if (is_lpss_ssp(drv_data)) {
if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff)
!= chip->lpss_rx_threshold)
@@ -1166,6 +1202,7 @@ static int setup(struct spi_device *spi)
break;
case LPSS_LPT_SSP:
case LPSS_BYT_SSP:
+ case LPSS_BSW_SSP:
case LPSS_SPT_SSP:
case LPSS_BXT_SSP:
config = lpss_get_config(drv_data);
@@ -1313,7 +1350,7 @@ static const struct acpi_device_id pxa2xx_spi_acpi_match[] = {
{ "INT3430", LPSS_LPT_SSP },
{ "INT3431", LPSS_LPT_SSP },
{ "80860F0E", LPSS_BYT_SSP },
- { "8086228E", LPSS_BYT_SSP },
+ { "8086228E", LPSS_BSW_SSP },
{ },
};
MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
@@ -1347,10 +1384,14 @@ static const struct pci_device_id pxa2xx_spi_pci_compound_match[] = {
/* SPT-H */
{ PCI_VDEVICE(INTEL, 0xa129), LPSS_SPT_SSP },
{ PCI_VDEVICE(INTEL, 0xa12a), LPSS_SPT_SSP },
- /* BXT */
+ /* 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 },
/* APL */
{ PCI_VDEVICE(INTEL, 0x5ac2), LPSS_BXT_SSP },
{ PCI_VDEVICE(INTEL, 0x5ac4), LPSS_BXT_SSP },
@@ -1438,6 +1479,29 @@ pxa2xx_spi_init_pdata(struct platform_device *pdev)
}
#endif
+static int pxa2xx_spi_fw_translate_cs(struct spi_master *master, unsigned cs)
+{
+ struct driver_data *drv_data = spi_master_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;
@@ -1490,6 +1554,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
master->setup = setup;
master->transfer_one_message = pxa2xx_spi_transfer_one_message;
master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
+ master->fw_translate_cs = pxa2xx_spi_fw_translate_cs;
master->auto_runtime_pm = true;
drv_data->ssp_type = ssp->type;
@@ -1576,6 +1641,8 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
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;
diff --git a/drivers/spi/spi-pxa2xx.h b/drivers/spi/spi-pxa2xx.h
index 58efa98313aa..a1ef88948144 100644
--- a/drivers/spi/spi-pxa2xx.h
+++ b/drivers/spi/spi-pxa2xx.h
@@ -69,8 +69,6 @@ struct driver_data {
void *rx;
void *rx_end;
int dma_mapped;
- dma_addr_t rx_dma;
- dma_addr_t tx_dma;
size_t rx_map_len;
size_t tx_map_len;
u8 n_bytes;
@@ -147,20 +145,9 @@ static inline void write_SSSR_CS(struct driver_data *drv_data, u32 val)
extern int pxa2xx_spi_flush(struct driver_data *drv_data);
extern void *pxa2xx_spi_next_transfer(struct driver_data *drv_data);
-/*
- * Select the right DMA implementation.
- */
-#if defined(CONFIG_SPI_PXA2XX_DMA)
-#define SPI_PXA2XX_USE_DMA 1
#define MAX_DMA_LEN SZ_64K
#define DEFAULT_DMA_CR1 (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL)
-#else
-#undef SPI_PXA2XX_USE_DMA
-#define MAX_DMA_LEN 0
-#define DEFAULT_DMA_CR1 0
-#endif
-#ifdef SPI_PXA2XX_USE_DMA
extern bool pxa2xx_spi_dma_is_possible(size_t len);
extern int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data);
extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data);
@@ -173,29 +160,5 @@ extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
u8 bits_per_word,
u32 *burst_code,
u32 *threshold);
-#else
-static inline bool pxa2xx_spi_dma_is_possible(size_t len) { return false; }
-static inline int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data)
-{
- return 0;
-}
-#define pxa2xx_spi_dma_transfer NULL
-static inline void pxa2xx_spi_dma_prepare(struct driver_data *drv_data,
- u32 dma_burst) {}
-static inline void pxa2xx_spi_dma_start(struct driver_data *drv_data) {}
-static inline int pxa2xx_spi_dma_setup(struct driver_data *drv_data)
-{
- return 0;
-}
-static inline void pxa2xx_spi_dma_release(struct driver_data *drv_data) {}
-static inline int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
- struct spi_device *spi,
- u8 bits_per_word,
- u32 *burst_code,
- u32 *threshold)
-{
- return -ENODEV;
-}
-#endif
#endif /* SPI_PXA2XX_H */
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index b30f03a99dfd..de2f2f90d799 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -144,6 +144,8 @@ SPI_STATISTICS_TRANSFER_BYTES_HISTO(14, "16384-32767");
SPI_STATISTICS_TRANSFER_BYTES_HISTO(15, "32768-65535");
SPI_STATISTICS_TRANSFER_BYTES_HISTO(16, "65536+");
+SPI_STATISTICS_SHOW(transfers_split_maxsize, "%lu");
+
static struct attribute *spi_dev_attrs[] = {
&dev_attr_modalias.attr,
NULL,
@@ -181,6 +183,7 @@ static struct attribute *spi_device_statistics_attrs[] = {
&dev_attr_spi_device_transfer_bytes_histo14.attr,
&dev_attr_spi_device_transfer_bytes_histo15.attr,
&dev_attr_spi_device_transfer_bytes_histo16.attr,
+ &dev_attr_spi_device_transfers_split_maxsize.attr,
NULL,
};
@@ -223,6 +226,7 @@ static struct attribute *spi_master_statistics_attrs[] = {
&dev_attr_spi_master_transfer_bytes_histo14.attr,
&dev_attr_spi_master_transfer_bytes_histo15.attr,
&dev_attr_spi_master_transfer_bytes_histo16.attr,
+ &dev_attr_spi_master_transfers_split_maxsize.attr,
NULL,
};
@@ -1024,6 +1028,8 @@ out:
if (msg->status && master->handle_err)
master->handle_err(master, msg);
+ spi_res_release(master, msg);
+
spi_finalize_current_message(master);
return ret;
@@ -2043,6 +2049,336 @@ struct spi_master *spi_busnum_to_master(u16 bus_num)
}
EXPORT_SYMBOL_GPL(spi_busnum_to_master);
+/*-------------------------------------------------------------------------*/
+
+/* Core methods for SPI resource management */
+
+/**
+ * spi_res_alloc - allocate a spi resource that is life-cycle managed
+ * during the processing of a spi_message while using
+ * spi_transfer_one
+ * @spi: the spi device for which we allocate memory
+ * @release: the release code to execute for this resource
+ * @size: size to alloc and return
+ * @gfp: GFP allocation flags
+ *
+ * Return: the pointer to the allocated data
+ *
+ * This may get enhanced in the future to allocate from a memory pool
+ * of the @spi_device or @spi_master to avoid repeated allocations.
+ */
+void *spi_res_alloc(struct spi_device *spi,
+ spi_res_release_t release,
+ size_t size, gfp_t gfp)
+{
+ struct spi_res *sres;
+
+ sres = kzalloc(sizeof(*sres) + size, gfp);
+ if (!sres)
+ return NULL;
+
+ INIT_LIST_HEAD(&sres->entry);
+ sres->release = release;
+
+ return sres->data;
+}
+EXPORT_SYMBOL_GPL(spi_res_alloc);
+
+/**
+ * spi_res_free - free an spi resource
+ * @res: pointer to the custom data of a resource
+ *
+ */
+void spi_res_free(void *res)
+{
+ struct spi_res *sres = container_of(res, struct spi_res, data);
+
+ if (!res)
+ return;
+
+ WARN_ON(!list_empty(&sres->entry));
+ kfree(sres);
+}
+EXPORT_SYMBOL_GPL(spi_res_free);
+
+/**
+ * spi_res_add - add a spi_res to the spi_message
+ * @message: the spi message
+ * @res: the spi_resource
+ */
+void spi_res_add(struct spi_message *message, void *res)
+{
+ struct spi_res *sres = container_of(res, struct spi_res, data);
+
+ WARN_ON(!list_empty(&sres->entry));
+ list_add_tail(&sres->entry, &message->resources);
+}
+EXPORT_SYMBOL_GPL(spi_res_add);
+
+/**
+ * spi_res_release - release all spi resources for this message
+ * @master: the @spi_master
+ * @message: the @spi_message
+ */
+void spi_res_release(struct spi_master *master,
+ struct spi_message *message)
+{
+ struct spi_res *res;
+
+ while (!list_empty(&message->resources)) {
+ res = list_last_entry(&message->resources,
+ struct spi_res, entry);
+
+ if (res->release)
+ res->release(master, message, res->data);
+
+ list_del(&res->entry);
+
+ kfree(res);
+ }
+}
+EXPORT_SYMBOL_GPL(spi_res_release);
+
+/*-------------------------------------------------------------------------*/
+
+/* Core methods for spi_message alterations */
+
+static void __spi_replace_transfers_release(struct spi_master *master,
+ struct spi_message *msg,
+ void *res)
+{
+ struct spi_replaced_transfers *rxfer = res;
+ size_t i;
+
+ /* call extra callback if requested */
+ if (rxfer->release)
+ rxfer->release(master, msg, res);
+
+ /* insert replaced transfers back into the message */
+ list_splice(&rxfer->replaced_transfers, rxfer->replaced_after);
+
+ /* remove the formerly inserted entries */
+ for (i = 0; i < rxfer->inserted; i++)
+ list_del(&rxfer->inserted_transfers[i].transfer_list);
+}
+
+/**
+ * spi_replace_transfers - replace transfers with several transfers
+ * and register change with spi_message.resources
+ * @msg: the spi_message we work upon
+ * @xfer_first: the first spi_transfer we want to replace
+ * @remove: number of transfers to remove
+ * @insert: the number of transfers we want to insert instead
+ * @release: extra release code necessary in some circumstances
+ * @extradatasize: extra data to allocate (with alignment guarantees
+ * of struct @spi_transfer)
+ * @gfp: gfp flags
+ *
+ * Returns: pointer to @spi_replaced_transfers,
+ * PTR_ERR(...) in case of errors.
+ */
+struct spi_replaced_transfers *spi_replace_transfers(
+ struct spi_message *msg,
+ struct spi_transfer *xfer_first,
+ size_t remove,
+ size_t insert,
+ spi_replaced_release_t release,
+ size_t extradatasize,
+ gfp_t gfp)
+{
+ struct spi_replaced_transfers *rxfer;
+ struct spi_transfer *xfer;
+ size_t i;
+
+ /* allocate the structure using spi_res */
+ rxfer = spi_res_alloc(msg->spi, __spi_replace_transfers_release,
+ insert * sizeof(struct spi_transfer)
+ + sizeof(struct spi_replaced_transfers)
+ + extradatasize,
+ gfp);
+ if (!rxfer)
+ return ERR_PTR(-ENOMEM);
+
+ /* the release code to invoke before running the generic release */
+ rxfer->release = release;
+
+ /* assign extradata */
+ if (extradatasize)
+ rxfer->extradata =
+ &rxfer->inserted_transfers[insert];
+
+ /* init the replaced_transfers list */
+ INIT_LIST_HEAD(&rxfer->replaced_transfers);
+
+ /* assign the list_entry after which we should reinsert
+ * the @replaced_transfers - it may be spi_message.messages!
+ */
+ rxfer->replaced_after = xfer_first->transfer_list.prev;
+
+ /* remove the requested number of transfers */
+ for (i = 0; i < remove; i++) {
+ /* if the entry after replaced_after it is msg->transfers
+ * then we have been requested to remove more transfers
+ * than are in the list
+ */
+ if (rxfer->replaced_after->next == &msg->transfers) {
+ dev_err(&msg->spi->dev,
+ "requested to remove more spi_transfers than are available\n");
+ /* insert replaced transfers back into the message */
+ list_splice(&rxfer->replaced_transfers,
+ rxfer->replaced_after);
+
+ /* free the spi_replace_transfer structure */
+ spi_res_free(rxfer);
+
+ /* and return with an error */
+ return ERR_PTR(-EINVAL);
+ }
+
+ /* remove the entry after replaced_after from list of
+ * transfers and add it to list of replaced_transfers
+ */
+ list_move_tail(rxfer->replaced_after->next,
+ &rxfer->replaced_transfers);
+ }
+
+ /* create copy of the given xfer with identical settings
+ * based on the first transfer to get removed
+ */
+ for (i = 0; i < insert; i++) {
+ /* we need to run in reverse order */
+ xfer = &rxfer->inserted_transfers[insert - 1 - i];
+
+ /* copy all spi_transfer data */
+ memcpy(xfer, xfer_first, sizeof(*xfer));
+
+ /* add to list */
+ list_add(&xfer->transfer_list, rxfer->replaced_after);
+
+ /* clear cs_change and delay_usecs for all but the last */
+ if (i) {
+ xfer->cs_change = false;
+ xfer->delay_usecs = 0;
+ }
+ }
+
+ /* set up inserted */
+ rxfer->inserted = insert;
+
+ /* and register it with spi_res/spi_message */
+ spi_res_add(msg, rxfer);
+
+ return rxfer;
+}
+EXPORT_SYMBOL_GPL(spi_replace_transfers);
+
+static int __spi_split_transfer_maxsize(struct spi_master *master,
+ struct spi_message *msg,
+ struct spi_transfer **xferp,
+ size_t maxsize,
+ gfp_t gfp)
+{
+ struct spi_transfer *xfer = *xferp, *xfers;
+ struct spi_replaced_transfers *srt;
+ size_t offset;
+ size_t count, i;
+
+ /* warn once about this fact that we are splitting a transfer */
+ dev_warn_once(&msg->spi->dev,
+ "spi_transfer of length %i exceed max length of %zu - needed to split transfers\n",
+ xfer->len, maxsize);
+
+ /* calculate how many we have to replace */
+ count = DIV_ROUND_UP(xfer->len, maxsize);
+
+ /* create replacement */
+ srt = spi_replace_transfers(msg, xfer, 1, count, NULL, 0, gfp);
+ if (IS_ERR(srt))
+ return PTR_ERR(srt);
+ xfers = srt->inserted_transfers;
+
+ /* now handle each of those newly inserted spi_transfers
+ * note that the replacements spi_transfers all are preset
+ * to the same values as *xferp, so tx_buf, rx_buf and len
+ * are all identical (as well as most others)
+ * so we just have to fix up len and the pointers.
+ *
+ * this also includes support for the depreciated
+ * spi_message.is_dma_mapped interface
+ */
+
+ /* the first transfer just needs the length modified, so we
+ * run it outside the loop
+ */
+ xfers[0].len = min_t(size_t, maxsize, xfer[0].len);
+
+ /* all the others need rx_buf/tx_buf also set */
+ for (i = 1, offset = maxsize; i < count; offset += maxsize, i++) {
+ /* update rx_buf, tx_buf and dma */
+ if (xfers[i].rx_buf)
+ xfers[i].rx_buf += offset;
+ if (xfers[i].rx_dma)
+ xfers[i].rx_dma += offset;
+ if (xfers[i].tx_buf)
+ xfers[i].tx_buf += offset;
+ if (xfers[i].tx_dma)
+ xfers[i].tx_dma += offset;
+
+ /* update length */
+ xfers[i].len = min(maxsize, xfers[i].len - offset);
+ }
+
+ /* we set up xferp to the last entry we have inserted,
+ * so that we skip those already split transfers
+ */
+ *xferp = &xfers[count - 1];
+
+ /* increment statistics counters */
+ SPI_STATISTICS_INCREMENT_FIELD(&master->statistics,
+ transfers_split_maxsize);
+ SPI_STATISTICS_INCREMENT_FIELD(&msg->spi->statistics,
+ transfers_split_maxsize);
+
+ return 0;
+}
+
+/**
+ * spi_split_tranfers_maxsize - split spi transfers into multiple transfers
+ * when an individual transfer exceeds a
+ * certain size
+ * @master: the @spi_master for this transfer
+ * @msg: the @spi_message to transform
+ * @maxsize: the maximum when to apply this
+ * @gfp: GFP allocation flags
+ *
+ * Return: status of transformation
+ */
+int spi_split_transfers_maxsize(struct spi_master *master,
+ struct spi_message *msg,
+ size_t maxsize,
+ gfp_t gfp)
+{
+ struct spi_transfer *xfer;
+ int ret;
+
+ /* iterate over the transfer_list,
+ * but note that xfer is advanced to the last transfer inserted
+ * to avoid checking sizes again unnecessarily (also xfer does
+ * potentiall belong to a different list by the time the
+ * replacement has happened
+ */
+ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+ if (xfer->len > maxsize) {
+ ret = __spi_split_transfer_maxsize(
+ master, msg, &xfer, maxsize, gfp);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(spi_split_transfers_maxsize);
/*-------------------------------------------------------------------------*/
diff --git a/include/linux/pxa2xx_ssp.h b/include/linux/pxa2xx_ssp.h
index c2f2574ff61c..2a097d176ba9 100644
--- a/include/linux/pxa2xx_ssp.h
+++ b/include/linux/pxa2xx_ssp.h
@@ -197,6 +197,7 @@ enum pxa_ssp_type {
QUARK_X1000_SSP,
LPSS_LPT_SSP, /* Keep LPSS types sorted with lpss_platforms[] */
LPSS_BYT_SSP,
+ LPSS_BSW_SSP,
LPSS_SPT_SSP,
LPSS_BXT_SSP,
};
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 06ea1c3a04d7..f54667b7b3c8 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -54,6 +54,10 @@ extern struct bus_type spi_bus_type;
*
* @transfer_bytes_histo:
* transfer bytes histogramm
+ *
+ * @transfers_split_maxsize:
+ * number of transfers that have been split because of
+ * maxsize limit
*/
struct spi_statistics {
spinlock_t lock; /* lock for the whole structure */
@@ -73,6 +77,8 @@ struct spi_statistics {
#define SPI_STATISTICS_HISTO_SIZE 17
unsigned long transfer_bytes_histo[SPI_STATISTICS_HISTO_SIZE];
+
+ unsigned long transfers_split_maxsize;
};
void spi_statistics_add_transfer_stats(struct spi_statistics *stats,
@@ -594,6 +600,37 @@ extern void spi_unregister_master(struct spi_master *master);
extern struct spi_master *spi_busnum_to_master(u16 busnum);
+/*
+ * SPI resource management while processing a SPI message
+ */
+
+/**
+ * struct spi_res - spi resource management structure
+ * @entry: list entry
+ * @release: release code called prior to freeing this resource
+ * @data: extra data allocated for the specific use-case
+ *
+ * this is based on ideas from devres, but focused on life-cycle
+ * management during spi_message processing
+ */
+typedef void (*spi_res_release_t)(struct spi_master *master,
+ struct spi_message *msg,
+ void *res);
+struct spi_res {
+ struct list_head entry;
+ spi_res_release_t release;
+ unsigned long long data[]; /* guarantee ull alignment */
+};
+
+extern void *spi_res_alloc(struct spi_device *spi,
+ spi_res_release_t release,
+ size_t size, gfp_t gfp);
+extern void spi_res_add(struct spi_message *message, void *res);
+extern void spi_res_free(void *res);
+
+extern void spi_res_release(struct spi_master *master,
+ struct spi_message *message);
+
/*---------------------------------------------------------------------------*/
/*
@@ -732,6 +769,7 @@ struct spi_transfer {
* @status: zero for success, else negative errno
* @queue: for use by whichever driver currently owns the message
* @state: for use by whichever driver currently owns the message
+ * @resources: for resource management when the spi message is processed
*
* A @spi_message is used to execute an atomic sequence of data transfers,
* each represented by a struct spi_transfer. The sequence is "atomic"
@@ -778,11 +816,15 @@ struct spi_message {
*/
struct list_head queue;
void *state;
+
+ /* list of spi_res reources when the spi message is processed */
+ struct list_head resources;
};
static inline void spi_message_init_no_memset(struct spi_message *m)
{
INIT_LIST_HEAD(&m->transfers);
+ INIT_LIST_HEAD(&m->resources);
}
static inline void spi_message_init(struct spi_message *m)
@@ -866,6 +908,60 @@ spi_max_transfer_size(struct spi_device *spi)
/*---------------------------------------------------------------------------*/
+/* SPI transfer replacement methods which make use of spi_res */
+
+struct spi_replaced_transfers;
+typedef void (*spi_replaced_release_t)(struct spi_master *master,
+ struct spi_message *msg,
+ struct spi_replaced_transfers *res);
+/**
+ * struct spi_replaced_transfers - structure describing the spi_transfer
+ * replacements that have occurred
+ * so that they can get reverted
+ * @release: some extra release code to get executed prior to
+ * relasing this structure
+ * @extradata: pointer to some extra data if requested or NULL
+ * @replaced_transfers: transfers that have been replaced and which need
+ * to get restored
+ * @replaced_after: the transfer after which the @replaced_transfers
+ * are to get re-inserted
+ * @inserted: number of transfers inserted
+ * @inserted_transfers: array of spi_transfers of array-size @inserted,
+ * that have been replacing replaced_transfers
+ *
+ * note: that @extradata will point to @inserted_transfers[@inserted]
+ * if some extra allocation is requested, so alignment will be the same
+ * as for spi_transfers
+ */
+struct spi_replaced_transfers {
+ spi_replaced_release_t release;
+ void *extradata;
+ struct list_head replaced_transfers;
+ struct list_head *replaced_after;
+ size_t inserted;
+ struct spi_transfer inserted_transfers[];
+};
+
+extern struct spi_replaced_transfers *spi_replace_transfers(
+ struct spi_message *msg,
+ struct spi_transfer *xfer_first,
+ size_t remove,
+ size_t insert,
+ spi_replaced_release_t release,
+ size_t extradatasize,
+ gfp_t gfp);
+
+/*---------------------------------------------------------------------------*/
+
+/* SPI transfer transformation methods */
+
+extern int spi_split_transfers_maxsize(struct spi_master *master,
+ struct spi_message *msg,
+ size_t maxsize,
+ gfp_t gfp);
+
+/*---------------------------------------------------------------------------*/
+
/* All these synchronous SPI transfer routines are utilities layered
* over the core async transfer primitive. Here, "synchronous" means
* they will sleep uninterruptibly until the async transfer completes.
OpenPOWER on IntegriCloud