soundwire: intel: Add Intel Master driver

Some Intel platforms have SoundWire Master, so add Intel SoundWire
Master driver which uses Cadence module. This patch adds probe and
initialization routines for Intel Master driver.

Signed-off-by: Hardik T Shah <[e-mail]>
Signed-off-by: Sanyog Kale <[e-mail]>
Reviewed-by: Philippe Ombredanne <[e-mail]>
Acked-By: Pierre-Louis Bossart <[e-mail]>
Reviewed-by: Takashi Iwai <[e-mail]>
Signed-off-by: Vinod Koul <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/soundwire/Kconfig

···
 config SOUNDWIRE_CADENCE
 	tristate
 
+config SOUNDWIRE_INTEL
+	tristate "Intel SoundWire Master driver"
+	select SOUNDWIRE_CADENCE
+	select SOUNDWIRE_BUS
+	depends on X86 && ACPI
+	---help---
+	  SoundWire Intel Master driver.
+	  If you have an Intel platform which has a SoundWire Master then
+	  enable this config option to get the SoundWire support for that
+	  device.
+
 endif

drivers/soundwire/Makefile

···
 #Cadence Objs
 soundwire-cadence-objs := cadence_master.o
 obj-$(CONFIG_SOUNDWIRE_CADENCE) += soundwire-cadence.o
+
+#Intel driver
+soundwire-intel-objs :=	intel.o
+obj-$(CONFIG_SOUNDWIRE_INTEL) += soundwire-intel.o

drivers/soundwire/intel.c

···
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2015-17 Intel Corporation.
+
+/*
+ * Soundwire Intel Master Driver
+ */
+
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/soundwire/sdw_registers.h>
+#include <linux/soundwire/sdw.h>
+#include <linux/soundwire/sdw_intel.h>
+#include "cadence_master.h"
+#include "intel.h"
+
+/* Intel SHIM Registers Definition */
+#define SDW_SHIM_LCAP			0x0
+#define SDW_SHIM_LCTL			0x4
+#define SDW_SHIM_IPPTR			0x8
+#define SDW_SHIM_SYNC			0xC
+
+#define SDW_SHIM_CTLSCAP(x)		(0x010 + 0x60 * x)
+#define SDW_SHIM_CTLS0CM(x)		(0x012 + 0x60 * x)
+#define SDW_SHIM_CTLS1CM(x)		(0x014 + 0x60 * x)
+#define SDW_SHIM_CTLS2CM(x)		(0x016 + 0x60 * x)
+#define SDW_SHIM_CTLS3CM(x)		(0x018 + 0x60 * x)
+#define SDW_SHIM_PCMSCAP(x)		(0x020 + 0x60 * x)
+
+#define SDW_SHIM_PCMSYCHM(x, y)		(0x022 + (0x60 * x) + (0x2 * y))
+#define SDW_SHIM_PCMSYCHC(x, y)		(0x042 + (0x60 * x) + (0x2 * y))
+#define SDW_SHIM_PDMSCAP(x)		(0x062 + 0x60 * x)
+#define SDW_SHIM_IOCTL(x)		(0x06C + 0x60 * x)
+#define SDW_SHIM_CTMCTL(x)		(0x06E + 0x60 * x)
+
+#define SDW_SHIM_WAKEEN			0x190
+#define SDW_SHIM_WAKESTS		0x192
+
+#define SDW_SHIM_LCTL_SPA		BIT(0)
+#define SDW_SHIM_LCTL_CPA		BIT(8)
+
+#define SDW_SHIM_SYNC_SYNCPRD_VAL	0x176F
+#define SDW_SHIM_SYNC_SYNCPRD		GENMASK(14, 0)
+#define SDW_SHIM_SYNC_SYNCCPU		BIT(15)
+#define SDW_SHIM_SYNC_CMDSYNC_MASK	GENMASK(19, 16)
+#define SDW_SHIM_SYNC_CMDSYNC		BIT(16)
+#define SDW_SHIM_SYNC_SYNCGO		BIT(24)
+
+#define SDW_SHIM_PCMSCAP_ISS		GENMASK(3, 0)
+#define SDW_SHIM_PCMSCAP_OSS		GENMASK(7, 4)
+#define SDW_SHIM_PCMSCAP_BSS		GENMASK(12, 8)
+
+#define SDW_SHIM_PCMSYCM_LCHN		GENMASK(3, 0)
+#define SDW_SHIM_PCMSYCM_HCHN		GENMASK(7, 4)
+#define SDW_SHIM_PCMSYCM_STREAM		GENMASK(13, 8)
+#define SDW_SHIM_PCMSYCM_DIR		BIT(15)
+
+#define SDW_SHIM_PDMSCAP_ISS		GENMASK(3, 0)
+#define SDW_SHIM_PDMSCAP_OSS		GENMASK(7, 4)
+#define SDW_SHIM_PDMSCAP_BSS		GENMASK(12, 8)
+#define SDW_SHIM_PDMSCAP_CPSS		GENMASK(15, 13)
+
+#define SDW_SHIM_IOCTL_MIF		BIT(0)
+#define SDW_SHIM_IOCTL_CO		BIT(1)
+#define SDW_SHIM_IOCTL_COE		BIT(2)
+#define SDW_SHIM_IOCTL_DO		BIT(3)
+#define SDW_SHIM_IOCTL_DOE		BIT(4)
+#define SDW_SHIM_IOCTL_BKE		BIT(5)
+#define SDW_SHIM_IOCTL_WPDD		BIT(6)
+#define SDW_SHIM_IOCTL_CIBD		BIT(8)
+#define SDW_SHIM_IOCTL_DIBD		BIT(9)
+
+#define SDW_SHIM_CTMCTL_DACTQE		BIT(0)
+#define SDW_SHIM_CTMCTL_DODS		BIT(1)
+#define SDW_SHIM_CTMCTL_DOAIS		GENMASK(4, 3)
+
+#define SDW_SHIM_WAKEEN_ENABLE		BIT(0)
+#define SDW_SHIM_WAKESTS_STATUS		BIT(0)
+
+/* Intel ALH Register definitions */
+#define SDW_ALH_STRMZCFG(x)		(0x000 + (0x4 * x))
+
+#define SDW_ALH_STRMZCFG_DMAT_VAL	0x3
+#define SDW_ALH_STRMZCFG_DMAT		GENMASK(7, 0)
+#define SDW_ALH_STRMZCFG_CHN		GENMASK(19, 16)
+
+struct sdw_intel {
+	struct sdw_cdns cdns;
+	int instance;
+	struct sdw_intel_link_res *res;
+};
+
+#define cdns_to_intel(_cdns) container_of(_cdns, struct sdw_intel, cdns)
+
+/*
+ * Read, write helpers for HW registers
+ */
+static inline int intel_readl(void __iomem *base, int offset)
+{
+	return readl(base + offset);
+}
+
+static inline void intel_writel(void __iomem *base, int offset, int value)
+{
+	writel(value, base + offset);
+}
+
+static inline u16 intel_readw(void __iomem *base, int offset)
+{
+	return readw(base + offset);
+}
+
+static inline void intel_writew(void __iomem *base, int offset, u16 value)
+{
+	writew(value, base + offset);
+}
+
+static int intel_clear_bit(void __iomem *base, int offset, u32 value, u32 mask)
+{
+	int timeout = 10;
+	u32 reg_read;
+
+	writel(value, base + offset);
+	do {
+		reg_read = readl(base + offset);
+		if (!(reg_read & mask))
+			return 0;
+
+		timeout--;
+		udelay(50);
+	} while (timeout != 0);
+
+	return -EAGAIN;
+}
+
+static int intel_set_bit(void __iomem *base, int offset, u32 value, u32 mask)
+{
+	int timeout = 10;
+	u32 reg_read;
+
+	writel(value, base + offset);
+	do {
+		reg_read = readl(base + offset);
+		if (reg_read & mask)
+			return 0;
+
+		timeout--;
+		udelay(50);
+	} while (timeout != 0);
+
+	return -EAGAIN;
+}
+
+/*
+ * shim ops
+ */
+
+static int intel_link_power_up(struct sdw_intel *sdw)
+{
+	unsigned int link_id = sdw->instance;
+	void __iomem *shim = sdw->res->shim;
+	int spa_mask, cpa_mask;
+	int link_control, ret;
+
+	/* Link power up sequence */
+	link_control = intel_readl(shim, SDW_SHIM_LCTL);
+	spa_mask = (SDW_SHIM_LCTL_SPA << link_id);
+	cpa_mask = (SDW_SHIM_LCTL_CPA << link_id);
+	link_control |=  spa_mask;
+
+	ret = intel_set_bit(shim, SDW_SHIM_LCTL, link_control, cpa_mask);
+	if (ret < 0)
+		return ret;
+
+	sdw->cdns.link_up = true;
+	return 0;
+}
+
+static int intel_shim_init(struct sdw_intel *sdw)
+{
+	void __iomem *shim = sdw->res->shim;
+	unsigned int link_id = sdw->instance;
+	int sync_reg, ret;
+	u16 ioctl = 0, act = 0;
+
+	/* Initialize Shim */
+	ioctl |= SDW_SHIM_IOCTL_BKE;
+	intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
+
+	ioctl |= SDW_SHIM_IOCTL_WPDD;
+	intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
+
+	ioctl |= SDW_SHIM_IOCTL_DO;
+	intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
+
+	ioctl |= SDW_SHIM_IOCTL_DOE;
+	intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
+
+	/* Switch to MIP from Glue logic */
+	ioctl = intel_readw(shim,  SDW_SHIM_IOCTL(link_id));
+
+	ioctl &= ~(SDW_SHIM_IOCTL_DOE);
+	intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
+
+	ioctl &= ~(SDW_SHIM_IOCTL_DO);
+	intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
+
+	ioctl |= (SDW_SHIM_IOCTL_MIF);
+	intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
+
+	ioctl &= ~(SDW_SHIM_IOCTL_BKE);
+	ioctl &= ~(SDW_SHIM_IOCTL_COE);
+
+	intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
+
+	act |= 0x1 << SDW_REG_SHIFT(SDW_SHIM_CTMCTL_DOAIS);
+	act |= SDW_SHIM_CTMCTL_DACTQE;
+	act |= SDW_SHIM_CTMCTL_DODS;
+	intel_writew(shim, SDW_SHIM_CTMCTL(link_id), act);
+
+	/* Now set SyncPRD period */
+	sync_reg = intel_readl(shim, SDW_SHIM_SYNC);
+	sync_reg |= (SDW_SHIM_SYNC_SYNCPRD_VAL <<
+			SDW_REG_SHIFT(SDW_SHIM_SYNC_SYNCPRD));
+
+	/* Set SyncCPU bit */
+	sync_reg |= SDW_SHIM_SYNC_SYNCCPU;
+	ret = intel_clear_bit(shim, SDW_SHIM_SYNC, sync_reg,
+				SDW_SHIM_SYNC_SYNCCPU);
+	if (ret < 0)
+		dev_err(sdw->cdns.dev, "Failed to set sync period: %d", ret);
+
+	return ret;
+}
+
+static int intel_prop_read(struct sdw_bus *bus)
+{
+	/* Initialize with default handler to read all DisCo properties */
+	sdw_master_read_prop(bus);
+
+	/* BIOS is not giving some values correctly. So, lets override them */
+	bus->prop.num_freq = 1;
+	bus->prop.freq = devm_kcalloc(bus->dev, sizeof(*bus->prop.freq),
+					bus->prop.num_freq, GFP_KERNEL);
+	if (!bus->prop.freq)
+		return -ENOMEM;
+
+	bus->prop.freq[0] = bus->prop.max_freq;
+	bus->prop.err_threshold = 5;
+
+	return 0;
+}
+
+/*
+ * probe and init
+ */
+static int intel_probe(struct platform_device *pdev)
+{
+	struct sdw_intel *sdw;
+	int ret;
+
+	sdw = devm_kzalloc(&pdev->dev, sizeof(*sdw), GFP_KERNEL);
+	if (!sdw)
+		return -ENOMEM;
+
+	sdw->instance = pdev->id;
+	sdw->res = dev_get_platdata(&pdev->dev);
+	sdw->cdns.dev = &pdev->dev;
+	sdw->cdns.registers = sdw->res->registers;
+	sdw->cdns.instance = sdw->instance;
+	sdw->cdns.msg_count = 0;
+	sdw->cdns.bus.dev = &pdev->dev;
+	sdw->cdns.bus.link_id = pdev->id;
+
+	sdw_cdns_probe(&sdw->cdns);
+
+	/* Set property read ops */
+	sdw_cdns_master_ops.read_prop = intel_prop_read;
+	sdw->cdns.bus.ops = &sdw_cdns_master_ops;
+
+	platform_set_drvdata(pdev, sdw);
+
+	ret = sdw_add_bus_master(&sdw->cdns.bus);
+	if (ret) {
+		dev_err(&pdev->dev, "sdw_add_bus_master fail: %d\n", ret);
+		goto err_master_reg;
+	}
+
+	/* Initialize shim and controller */
+	intel_link_power_up(sdw);
+	intel_shim_init(sdw);
+
+	ret = sdw_cdns_init(&sdw->cdns);
+	if (ret)
+		goto err_init;
+
+	sdw_cdns_enable_interrupt(&sdw->cdns);
+	if (ret)
+		goto err_init;
+
+	/* Acquire IRQ */
+	ret = request_threaded_irq(sdw->res->irq, sdw_cdns_irq,
+			sdw_cdns_thread, IRQF_SHARED, KBUILD_MODNAME,
+			&sdw->cdns);
+	if (ret < 0) {
+		dev_err(sdw->cdns.dev, "unable to grab IRQ %d, disabling device\n",
+				sdw->res->irq);
+		goto err_init;
+	}
+
+	return 0;
+
+err_init:
+	sdw_delete_bus_master(&sdw->cdns.bus);
+err_master_reg:
+	return ret;
+}
+
+static int intel_remove(struct platform_device *pdev)
+{
+	struct sdw_intel *sdw;
+
+	sdw = platform_get_drvdata(pdev);
+
+	free_irq(sdw->res->irq, sdw);
+	sdw_delete_bus_master(&sdw->cdns.bus);
+
+	return 0;
+}
+
+static struct platform_driver sdw_intel_drv = {
+	.probe = intel_probe,
+	.remove = intel_remove,
+	.driver = {
+		.name = "int-sdw",
+
+	},
+};
+
+module_platform_driver(sdw_intel_drv);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS("platform:int-sdw");
+MODULE_DESCRIPTION("Intel Soundwire Master Driver");

drivers/soundwire/intel.h

···
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2015-17 Intel Corporation.
+
+#ifndef __SDW_INTEL_LOCAL_H
+#define __SDW_INTEL_LOCAL_H
+
+/**
+ * struct sdw_intel_res - Soundwire link resources
+ * @registers: Link IO registers base
+ * @shim: Audio shim pointer
+ * @alh: ALH (Audio Link Hub) pointer
+ * @irq: Interrupt line
+ *
+ * This is set as pdata for each link instance.
+ */
+struct sdw_intel_link_res {
+	void __iomem *registers;
+	void __iomem *shim;
+	void __iomem *alh;
+	int irq;
+};
+
+#endif /* __SDW_INTEL_LOCAL_H */

include/linux/soundwire/sdw_intel.h

···
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2015-17 Intel Corporation.
+
+#ifndef __SDW_INTEL_H
+#define __SDW_INTEL_H
+
+/**
+ * struct sdw_intel_res - Soundwire Intel resource structure
+ * @mmio_base: mmio base of SoundWire registers
+ * @irq: interrupt number
+ * @handle: ACPI parent handle
+ * @parent: parent device
+ */
+struct sdw_intel_res {
+	void __iomem *mmio_base;
+	int irq;
+	acpi_handle handle;
+	struct device *parent;
+};
+
+#endif