--- /dev/null
+From b518f18f89dbd49fe9403a8c92230f1af59219bc Mon Sep 17 00:00:00 2001
+From: Chuanhong Guo <gch981213@gmail.com>
+Date: Wed, 5 Feb 2020 18:25:37 +0800
+Subject: [PATCH 1/2] spi: add driver for ar934x spi controller
+
+This patch adds driver for SPI controller found in Qualcomm Atheros
+AR934x/QCA95xx SoCs.
+This controller is a superset of the already supported qca,ar7100-spi.
+Besides the bit-bang mode in spi-ath79.c, this new controller added
+a new "shift register" mode, allowing faster spi operations.
+
+Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
+---
+ drivers/spi/Kconfig | 7 ++
+ drivers/spi/Makefile | 1 +
+ drivers/spi/spi-ar934x.c | 229 +++++++++++++++++++++++++++++++++++++++
+ 3 files changed, 237 insertions(+)
+ create mode 100644 drivers/spi/spi-ar934x.c
+
+--- a/drivers/spi/Kconfig
++++ b/drivers/spi/Kconfig
+@@ -61,6 +61,13 @@ config SPI_ALTERA
+ help
+ This is the driver for the Altera SPI Controller.
+
++config SPI_AR934X
++ tristate "Qualcomm Atheros AR934X/QCA95XX SPI controller driver"
++ depends on ATH79 || COMPILE_TEST
++ help
++ This enables support for the SPI controller present on the
++ Qualcomm Atheros AR934X/QCA95XX SoCs.
++
+ config SPI_ATH79
+ tristate "Atheros AR71XX/AR724X/AR913X SPI controller driver"
+ depends on ATH79 && GPIOLIB
+--- a/drivers/spi/Makefile
++++ b/drivers/spi/Makefile
+@@ -14,6 +14,7 @@ obj-$(CONFIG_SPI_LOOPBACK_TEST) += spi-
+
+ # SPI master controller drivers (bus)
+ obj-$(CONFIG_SPI_ALTERA) += spi-altera.o
++obj-$(CONFIG_SPI_AR934X) += spi-ar934x.o
+ obj-$(CONFIG_SPI_ARMADA_3700) += spi-armada-3700.o
+ obj-$(CONFIG_SPI_ATMEL) += spi-atmel.o
+ obj-$(CONFIG_SPI_ATH79) += spi-ath79.o
+--- /dev/null
++++ b/drivers/spi/spi-ar934x.c
+@@ -0,0 +1,229 @@
++// SPDX-License-Identifier: GPL-2.0
++//
++// SPI controller driver for Qualcomm Atheros AR934x/QCA95xx SoCs
++//
++// Copyright (C) 2020 Chuanhong Guo <gch981213@gmail.com>
++//
++// Based on spi-mt7621.c:
++// Copyright (C) 2011 Sergiy <piratfm@gmail.com>
++// Copyright (C) 2011-2013 Gabor Juhos <juhosg@openwrt.org>
++// Copyright (C) 2014-2015 Felix Fietkau <nbd@nbd.name>
++
++#include <linux/clk.h>
++#include <linux/io.h>
++#include <linux/iopoll.h>
++#include <linux/kernel.h>
++#include <linux/module.h>
++#include <linux/of_device.h>
++#include <linux/spi/spi.h>
++
++#define DRIVER_NAME "spi-ar934x"
++
++#define AR934X_SPI_REG_FS 0x00
++#define AR934X_SPI_ENABLE BIT(0)
++
++#define AR934X_SPI_REG_CTRL 0x04
++#define AR934X_SPI_CLK_MASK GENMASK(5, 0)
++
++#define AR934X_SPI_DATAOUT 0x10
++
++#define AR934X_SPI_REG_SHIFT_CTRL 0x14
++#define AR934X_SPI_SHIFT_EN BIT(31)
++#define AR934X_SPI_SHIFT_CS(n) BIT(28 + (n))
++#define AR934X_SPI_SHIFT_TERM 26
++#define AR934X_SPI_SHIFT_VAL(cs, term, count) \
++ (AR934X_SPI_SHIFT_EN | AR934X_SPI_SHIFT_CS(cs) | \
++ (term) << AR934X_SPI_SHIFT_TERM | (count))
++
++#define AR934X_SPI_DATAIN 0x18
++
++struct ar934x_spi {
++ struct spi_controller *ctlr;
++ void __iomem *base;
++ struct clk *clk;
++ unsigned int clk_freq;
++};
++
++static inline int ar934x_spi_clk_div(struct ar934x_spi *sp, unsigned int freq)
++{
++ int div = DIV_ROUND_UP(sp->clk_freq, freq * 2) - 1;
++
++ if (div < 0)
++ return 0;
++ else if (div > AR934X_SPI_CLK_MASK)
++ return -EINVAL;
++ else
++ return div;
++}
++
++static int ar934x_spi_setup(struct spi_device *spi)
++{
++ struct ar934x_spi *sp = spi_controller_get_devdata(spi->master);
++
++ if ((spi->max_speed_hz == 0) ||
++ (spi->max_speed_hz > (sp->clk_freq / 2))) {
++ spi->max_speed_hz = sp->clk_freq / 2;
++ } else if (spi->max_speed_hz < (sp->clk_freq / 128)) {
++ dev_err(&spi->dev, "spi clock is too low\n");
++ return -EINVAL;
++ }
++
++ return 0;
++}
++
++static int ar934x_spi_transfer_one_message(struct spi_controller *master,
++ struct spi_message *m)
++{
++ struct ar934x_spi *sp = spi_controller_get_devdata(master);
++ struct spi_transfer *t = NULL;
++ struct spi_device *spi = m->spi;
++ unsigned long trx_done, trx_cur;
++ int stat = 0;
++ u8 term = 0;
++ int div, i;
++ u32 reg;
++ const u8 *tx_buf;
++ u8 *buf;
++
++ m->actual_length = 0;
++ list_for_each_entry(t, &m->transfers, transfer_list) {
++ if (t->speed_hz)
++ div = ar934x_spi_clk_div(sp, t->speed_hz);
++ else
++ div = ar934x_spi_clk_div(sp, spi->max_speed_hz);
++ if (div < 0) {
++ stat = -EIO;
++ goto msg_done;
++ }
++
++ reg = ioread32(sp->base + AR934X_SPI_REG_CTRL);
++ reg &= ~AR934X_SPI_CLK_MASK;
++ reg |= div;
++ iowrite32(reg, sp->base + AR934X_SPI_REG_CTRL);
++ iowrite32(0, sp->base + AR934X_SPI_DATAOUT);
++
++ for (trx_done = 0; trx_done < t->len; trx_done += 4) {
++ trx_cur = t->len - trx_done;
++ if (trx_cur > 4)
++ trx_cur = 4;
++ else if (list_is_last(&t->transfer_list, &m->transfers))
++ term = 1;
++
++ if (t->tx_buf) {
++ tx_buf = t->tx_buf + trx_done;
++ reg = tx_buf[0];
++ for (i = 1; i < trx_cur; i++)
++ reg = reg << 8 | tx_buf[i];
++ iowrite32(reg, sp->base + AR934X_SPI_DATAOUT);
++ }
++
++ reg = AR934X_SPI_SHIFT_VAL(spi->chip_select, term,
++ trx_cur * 8);
++ iowrite32(reg, sp->base + AR934X_SPI_REG_SHIFT_CTRL);
++ stat = readl_poll_timeout(
++ sp->base + AR934X_SPI_REG_SHIFT_CTRL, reg,
++ !(reg & AR934X_SPI_SHIFT_EN), 0, 5);
++ if (stat < 0)
++ goto msg_done;
++
++ if (t->rx_buf) {
++ reg = ioread32(sp->base + AR934X_SPI_DATAIN);
++ buf = t->rx_buf + trx_done;
++ for (i = 0; i < trx_cur; i++) {
++ buf[trx_cur - i - 1] = reg & 0xff;
++ reg >>= 8;
++ }
++ }
++ }
++ m->actual_length += t->len;
++ }
++
++msg_done:
++ m->status = stat;
++ spi_finalize_current_message(master);
++
++ return 0;
++}
++
++static const struct of_device_id ar934x_spi_match[] = {
++ { .compatible = "qca,ar934x-spi" },
++ {},
++};
++MODULE_DEVICE_TABLE(of, ar934x_spi_match);
++
++static int ar934x_spi_probe(struct platform_device *pdev)
++{
++ struct spi_controller *ctlr;
++ struct ar934x_spi *sp;
++ void __iomem *base;
++ struct clk *clk;
++ int ret;
++
++ base = devm_platform_ioremap_resource(pdev, 0);
++ if (IS_ERR(base))
++ return PTR_ERR(base);
++
++ clk = devm_clk_get(&pdev->dev, NULL);
++ if (IS_ERR(clk)) {
++ dev_err(&pdev->dev, "failed to get clock\n");
++ return PTR_ERR(clk);
++ }
++
++ ret = clk_prepare_enable(clk);
++ if (ret)
++ return ret;
++
++ ctlr = spi_alloc_master(&pdev->dev, sizeof(*sp));
++ if (!ctlr) {
++ dev_info(&pdev->dev, "failed to allocate spi controller\n");
++ return -ENOMEM;
++ }
++
++ iowrite32(AR934X_SPI_ENABLE, base + AR934X_SPI_REG_FS);
++
++ ctlr->mode_bits = SPI_LSB_FIRST;
++ ctlr->setup = ar934x_spi_setup;
++ ctlr->transfer_one_message = ar934x_spi_transfer_one_message;
++ ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
++ ctlr->dev.of_node = pdev->dev.of_node;
++ ctlr->num_chipselect = 3;
++
++ dev_set_drvdata(&pdev->dev, ctlr);
++
++ sp = spi_controller_get_devdata(ctlr);
++ sp->base = base;
++ sp->clk = clk;
++ sp->clk_freq = clk_get_rate(clk);
++ sp->ctlr = ctlr;
++
++ return devm_spi_register_controller(&pdev->dev, ctlr);
++}
++
++static int ar934x_spi_remove(struct platform_device *pdev)
++{
++ struct spi_controller *ctlr;
++ struct ar934x_spi *sp;
++
++ ctlr = dev_get_drvdata(&pdev->dev);
++ sp = spi_controller_get_devdata(ctlr);
++
++ clk_disable_unprepare(sp->clk);
++
++ return 0;
++}
++
++static struct platform_driver ar934x_spi_driver = {
++ .driver = {
++ .name = DRIVER_NAME,
++ .of_match_table = ar934x_spi_match,
++ },
++ .probe = ar934x_spi_probe,
++ .remove = ar934x_spi_remove,
++};
++
++module_platform_driver(ar934x_spi_driver);
++
++MODULE_DESCRIPTION("SPI controller driver for Qualcomm Atheros AR934x/QCA95xx");
++MODULE_AUTHOR("Chuanhong Guo <gch981213@gmail.com>");
++MODULE_LICENSE("GPL v2");
++MODULE_ALIAS("platform:" DRIVER_NAME);
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