media: atmel: atmel-isc: split driver into driver base and isc

This splits the Atmel ISC driver into a common base: atmel-isc-base.c
and the driver probe/dt part , atmel-sama5d2-isc.c
This is needed to keep a common ground for the sensor controller which will
be reused.
The atmel-isc will use the common symbols inside the atmel-isc-base
Future driver will also use the same symbols and redefine different aspects,
for a different version of the ISC.
This is done to avoid complete code duplication by creating a totally
different driver for the new variant of the ISC.
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil-cisco@xs4all.nl: folded 'atmel: atmel-sama5d2-isc: fixed checkpatch warnings' into this patch]
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

MAINTAINERS

@@ -10296,7 +10296,9 @@ MICROCHIP ISC DRIVER
 M:	Eugen Hristev <eugen.hristev@microchip.com>
 L:	linux-media@vger.kernel.org
 S:	Supported
-F:	drivers/media/platform/atmel/atmel-isc.c
+F:	drivers/media/platform/atmel/atmel-sama5d2-isc.c
+F:	drivers/media/platform/atmel/atmel-isc.h
+F:	drivers/media/platform/atmel/atmel-isc-base.c
 F:	drivers/media/platform/atmel/atmel-isc-regs.h
 F:	Documentation/devicetree/bindings/media/atmel-isc.txt
 

drivers/media/platform/atmel/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
-obj-$(CONFIG_VIDEO_ATMEL_ISC) += atmel-isc.o
+atmel-isc-objs = atmel-sama5d2-isc.o atmel-isc-base.o
+
 obj-$(CONFIG_VIDEO_ATMEL_ISI) += atmel-isi.o
+obj-$(CONFIG_VIDEO_ATMEL_ISC) += atmel-isc.o

drivers/media/platform/atmel/atmel-isc.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Microchip Image Sensor Controller (ISC) driver header file
+ *
+ * Copyright (C) 2016-2019 Microchip Technology, Inc.
+ *
+ * Author: Songjun Wu
+ * Author: Eugen Hristev <eugen.hristev@microchip.com>
+ *
+ */
+#ifndef _ATMEL_ISC_H_
+
+#define ISC_MAX_SUPPORT_WIDTH   2592
+#define ISC_MAX_SUPPORT_HEIGHT  1944
+
+#define ISC_CLK_MAX_DIV		255
+
+enum isc_clk_id {
+	ISC_ISPCK = 0,
+	ISC_MCK = 1,
+};
+
+struct isc_clk {
+	struct clk_hw   hw;
+	struct clk      *clk;
+	struct regmap   *regmap;
+	spinlock_t	lock;	/* serialize access to clock registers */
+	u8		id;
+	u8		parent_id;
+	u32		div;
+	struct device	*dev;
+};
+
+#define to_isc_clk(v) container_of(v, struct isc_clk, hw)
+
+struct isc_buffer {
+	struct vb2_v4l2_buffer  vb;
+	struct list_head	list;
+};
+
+struct isc_subdev_entity {
+	struct v4l2_subdev		*sd;
+	struct v4l2_async_subdev	*asd;
+	struct v4l2_async_notifier      notifier;
+
+	u32 pfe_cfg0;
+
+	struct list_head list;
+};
+
+/*
+ * struct isc_format - ISC media bus format information
+			This structure represents the interface between the ISC
+			and the sensor. It's the input format received by
+			the ISC.
+ * @fourcc:		Fourcc code for this format
+ * @mbus_code:		V4L2 media bus format code.
+ * @cfa_baycfg:		If this format is RAW BAYER, indicate the type of bayer.
+			this is either BGBG, RGRG, etc.
+ * @pfe_cfg0_bps:	Number of hardware data lines connected to the ISC
+ */
+
+struct isc_format {
+	u32	fourcc;
+	u32	mbus_code;
+	u32	cfa_baycfg;
+
+	bool	sd_support;
+	u32	pfe_cfg0_bps;
+};
+
+/* Pipeline bitmap */
+#define WB_ENABLE	BIT(0)
+#define CFA_ENABLE	BIT(1)
+#define CC_ENABLE	BIT(2)
+#define GAM_ENABLE	BIT(3)
+#define GAM_BENABLE	BIT(4)
+#define GAM_GENABLE	BIT(5)
+#define GAM_RENABLE	BIT(6)
+#define CSC_ENABLE	BIT(7)
+#define CBC_ENABLE	BIT(8)
+#define SUB422_ENABLE	BIT(9)
+#define SUB420_ENABLE	BIT(10)
+
+#define GAM_ENABLES	(GAM_RENABLE | GAM_GENABLE | GAM_BENABLE | GAM_ENABLE)
+
+/*
+ * struct fmt_config - ISC format configuration and internal pipeline
+			This structure represents the internal configuration
+			of the ISC.
+			It also holds the format that ISC will present to v4l2.
+ * @sd_format:		Pointer to an isc_format struct that holds the sensor
+			configuration.
+ * @fourcc:		Fourcc code for this format.
+ * @bpp:		Bytes per pixel in the current format.
+ * @rlp_cfg_mode:	Configuration of the RLP (rounding, limiting packaging)
+ * @dcfg_imode:		Configuration of the input of the DMA module
+ * @dctrl_dview:	Configuration of the output of the DMA module
+ * @bits_pipeline:	Configuration of the pipeline, which modules are enabled
+ */
+struct fmt_config {
+	struct isc_format	*sd_format;
+
+	u32			fourcc;
+	u8			bpp;
+
+	u32			rlp_cfg_mode;
+	u32			dcfg_imode;
+	u32			dctrl_dview;
+
+	u32			bits_pipeline;
+};
+
+#define HIST_ENTRIES		512
+#define HIST_BAYER		(ISC_HIS_CFG_MODE_B + 1)
+
+enum{
+	HIST_INIT = 0,
+	HIST_ENABLED,
+	HIST_DISABLED,
+};
+
+struct isc_ctrls {
+	struct v4l2_ctrl_handler handler;
+
+	u32 brightness;
+	u32 contrast;
+	u8 gamma_index;
+#define ISC_WB_NONE	0
+#define ISC_WB_AUTO	1
+#define ISC_WB_ONETIME	2
+	u8 awb;
+
+	/* one for each component : GR, R, GB, B */
+	u32 gain[HIST_BAYER];
+	u32 offset[HIST_BAYER];
+
+	u32 hist_entry[HIST_ENTRIES];
+	u32 hist_count[HIST_BAYER];
+	u8 hist_id;
+	u8 hist_stat;
+#define HIST_MIN_INDEX		0
+#define HIST_MAX_INDEX		1
+	u32 hist_minmax[HIST_BAYER][2];
+};
+
+#define ISC_PIPE_LINE_NODE_NUM	11
+
+/*
+ * struct isc_device - ISC device driver data/config struct
+ * @regmap:		Register map
+ * @hclock:		Hclock clock input (refer datasheet)
+ * @ispck:		iscpck clock (refer datasheet)
+ * @isc_clks:		ISC clocks
+ *
+ * @dev:		Registered device driver
+ * @v4l2_dev:		v4l2 registered device
+ * @video_dev:		registered video device
+ *
+ * @vb2_vidq:		video buffer 2 video queue
+ * @dma_queue_lock:	lock to serialize the dma buffer queue
+ * @dma_queue:		the queue for dma buffers
+ * @cur_frm:		current isc frame/buffer
+ * @sequence:		current frame number
+ * @stop:		true if isc is not streaming, false if streaming
+ * @comp:		completion reference that signals frame completion
+ *
+ * @fmt:		current v42l format
+ * @user_formats:	list of formats that are supported and agreed with sd
+ * @num_user_formats:	how many formats are in user_formats
+ *
+ * @config:		current ISC format configuration
+ * @try_config:		the current ISC try format , not yet activated
+ *
+ * @ctrls:		holds information about ISC controls
+ * @do_wb_ctrl:		control regarding the DO_WHITE_BALANCE button
+ * @awb_work:		workqueue reference for autowhitebalance histogram
+ *			analysis
+ *
+ * @lock:		lock for serializing userspace file operations
+ *			with ISC operations
+ * @awb_lock:		lock for serializing awb work queue operations
+ *			with DMA/buffer operations
+ *
+ * @pipeline:		configuration of the ISC pipeline
+ *
+ * @current_subdev:	current subdevice: the sensor
+ * @subdev_entities:	list of subdevice entitites
+ */
+struct isc_device {
+	struct regmap		*regmap;
+	struct clk		*hclock;
+	struct clk		*ispck;
+	struct isc_clk		isc_clks[2];
+
+	struct device		*dev;
+	struct v4l2_device	v4l2_dev;
+	struct video_device	video_dev;
+
+	struct vb2_queue	vb2_vidq;
+	spinlock_t		dma_queue_lock; /* serialize access to dma queue */
+	struct list_head	dma_queue;
+	struct isc_buffer	*cur_frm;
+	unsigned int		sequence;
+	bool			stop;
+	struct completion	comp;
+
+	struct v4l2_format	fmt;
+	struct isc_format	**user_formats;
+	unsigned int		num_user_formats;
+
+	struct fmt_config	config;
+	struct fmt_config	try_config;
+
+	struct isc_ctrls	ctrls;
+	struct v4l2_ctrl	*do_wb_ctrl;
+	struct work_struct	awb_work;
+
+	struct mutex		lock; /* serialize access to file operations */
+	spinlock_t		awb_lock; /* serialize access to DMA buffers from awb work queue */
+
+	struct regmap_field	*pipeline[ISC_PIPE_LINE_NODE_NUM];
+
+	struct isc_subdev_entity	*current_subdev;
+	struct list_head		subdev_entities;
+};
+
+#define GAMMA_MAX	2
+#define GAMMA_ENTRIES	64
+
+#define ATMEL_ISC_NAME "atmel-isc"
+
+/* module parameters */
+extern unsigned int debug;
+extern unsigned int sensor_preferred;
+
+extern struct isc_format formats_list[];
+extern struct isc_format controller_formats[];
+extern const u32 isc_gamma_table[GAMMA_MAX + 1][GAMMA_ENTRIES];
+extern const struct regmap_config isc_regmap_config;
+extern const struct v4l2_async_notifier_operations isc_async_ops;
+
+irqreturn_t isc_interrupt(int irq, void *dev_id);
+int isc_pipeline_init(struct isc_device *isc);
+int isc_clk_init(struct isc_device *isc);
+void isc_subdev_cleanup(struct isc_device *isc);
+void isc_clk_cleanup(struct isc_device *isc);
+
+#endif

drivers/media/platform/atmel/atmel-sama5d2-isc.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microchip Image Sensor Controller (ISC) driver
+ *
+ * Copyright (C) 2016-2019 Microchip Technology, Inc.
+ *
+ * Author: Songjun Wu
+ * Author: Eugen Hristev <eugen.hristev@microchip.com>
+ *
+ *
+ * Sensor-->PFE-->WB-->CFA-->CC-->GAM-->CSC-->CBC-->SUB-->RLP-->DMA
+ *
+ * ISC video pipeline integrates the following submodules:
+ * PFE: Parallel Front End to sample the camera sensor input stream
+ *  WB: Programmable white balance in the Bayer domain
+ * CFA: Color filter array interpolation module
+ *  CC: Programmable color correction
+ * GAM: Gamma correction
+ * CSC: Programmable color space conversion
+ * CBC: Contrast and Brightness control
+ * SUB: This module performs YCbCr444 to YCbCr420 chrominance subsampling
+ * RLP: This module performs rounding, range limiting
+ *      and packing of the incoming data
+ */
+
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/videodev2.h>
+
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-image-sizes.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-subdev.h>
+#include <media/videobuf2-dma-contig.h>
+
+#include "atmel-isc-regs.h"
+#include "atmel-isc.h"
+
+#define ISC_MAX_SUPPORT_WIDTH   2592
+#define ISC_MAX_SUPPORT_HEIGHT  1944
+
+#define ISC_CLK_MAX_DIV		255
+
+static int isc_parse_dt(struct device *dev, struct isc_device *isc)
+{
+	struct device_node *np = dev->of_node;
+	struct device_node *epn = NULL, *rem;
+	struct isc_subdev_entity *subdev_entity;
+	unsigned int flags;
+	int ret;
+
+	INIT_LIST_HEAD(&isc->subdev_entities);
+
+	while (1) {
+		struct v4l2_fwnode_endpoint v4l2_epn = { .bus_type = 0 };
+
+		epn = of_graph_get_next_endpoint(np, epn);
+		if (!epn)
+			return 0;
+
+		rem = of_graph_get_remote_port_parent(epn);
+		if (!rem) {
+			dev_notice(dev, "Remote device at %pOF not found\n",
+				   epn);
+			continue;
+		}
+
+		ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(epn),
+						 &v4l2_epn);
+		if (ret) {
+			of_node_put(rem);
+			ret = -EINVAL;
+			dev_err(dev, "Could not parse the endpoint\n");
+			break;
+		}
+
+		subdev_entity = devm_kzalloc(dev, sizeof(*subdev_entity),
+					     GFP_KERNEL);
+		if (!subdev_entity) {
+			of_node_put(rem);
+			ret = -ENOMEM;
+			break;
+		}
+
+		/* asd will be freed by the subsystem once it's added to the
+		 * notifier list
+		 */
+		subdev_entity->asd = kzalloc(sizeof(*subdev_entity->asd),
+					     GFP_KERNEL);
+		if (!subdev_entity->asd) {
+			of_node_put(rem);
+			ret = -ENOMEM;
+			break;
+		}
+
+		flags = v4l2_epn.bus.parallel.flags;
+
+		if (flags & V4L2_MBUS_HSYNC_ACTIVE_LOW)
+			subdev_entity->pfe_cfg0 = ISC_PFE_CFG0_HPOL_LOW;
+
+		if (flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)
+			subdev_entity->pfe_cfg0 |= ISC_PFE_CFG0_VPOL_LOW;
+
+		if (flags & V4L2_MBUS_PCLK_SAMPLE_FALLING)
+			subdev_entity->pfe_cfg0 |= ISC_PFE_CFG0_PPOL_LOW;
+
+		if (v4l2_epn.bus_type == V4L2_MBUS_BT656)
+			subdev_entity->pfe_cfg0 |= ISC_PFE_CFG0_CCIR_CRC |
+					ISC_PFE_CFG0_CCIR656;
+
+		subdev_entity->asd->match_type = V4L2_ASYNC_MATCH_FWNODE;
+		subdev_entity->asd->match.fwnode =
+			of_fwnode_handle(rem);
+		list_add_tail(&subdev_entity->list, &isc->subdev_entities);
+	}
+
+	of_node_put(epn);
+	return ret;
+}
+
+static int atmel_isc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct isc_device *isc;
+	struct resource *res;
+	void __iomem *io_base;
+	struct isc_subdev_entity *subdev_entity;
+	int irq;
+	int ret;
+
+	isc = devm_kzalloc(dev, sizeof(*isc), GFP_KERNEL);
+	if (!isc)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, isc);
+	isc->dev = dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	io_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(io_base))
+		return PTR_ERR(io_base);
+
+	isc->regmap = devm_regmap_init_mmio(dev, io_base, &isc_regmap_config);
+	if (IS_ERR(isc->regmap)) {
+		ret = PTR_ERR(isc->regmap);
+		dev_err(dev, "failed to init register map: %d\n", ret);
+		return ret;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		ret = irq;
+		dev_err(dev, "failed to get irq: %d\n", ret);
+		return ret;
+	}
+
+	ret = devm_request_irq(dev, irq, isc_interrupt, 0,
+			       ATMEL_ISC_NAME, isc);
+	if (ret < 0) {
+		dev_err(dev, "can't register ISR for IRQ %u (ret=%i)\n",
+			irq, ret);
+		return ret;
+	}
+
+	ret = isc_pipeline_init(isc);
+	if (ret)
+		return ret;
+
+	isc->hclock = devm_clk_get(dev, "hclock");
+	if (IS_ERR(isc->hclock)) {
+		ret = PTR_ERR(isc->hclock);
+		dev_err(dev, "failed to get hclock: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_prepare_enable(isc->hclock);
+	if (ret) {
+		dev_err(dev, "failed to enable hclock: %d\n", ret);
+		return ret;
+	}
+
+	ret = isc_clk_init(isc);
+	if (ret) {
+		dev_err(dev, "failed to init isc clock: %d\n", ret);
+		goto unprepare_hclk;
+	}
+
+	isc->ispck = isc->isc_clks[ISC_ISPCK].clk;
+
+	ret = clk_prepare_enable(isc->ispck);
+	if (ret) {
+		dev_err(dev, "failed to enable ispck: %d\n", ret);
+		goto unprepare_hclk;
+	}
+
+	/* ispck should be greater or equal to hclock */
+	ret = clk_set_rate(isc->ispck, clk_get_rate(isc->hclock));
+	if (ret) {
+		dev_err(dev, "failed to set ispck rate: %d\n", ret);
+		goto unprepare_clk;
+	}
+
+	ret = v4l2_device_register(dev, &isc->v4l2_dev);
+	if (ret) {
+		dev_err(dev, "unable to register v4l2 device.\n");
+		goto unprepare_clk;
+	}
+
+	ret = isc_parse_dt(dev, isc);
+	if (ret) {
+		dev_err(dev, "fail to parse device tree\n");
+		goto unregister_v4l2_device;
+	}
+
+	if (list_empty(&isc->subdev_entities)) {
+		dev_err(dev, "no subdev found\n");
+		ret = -ENODEV;
+		goto unregister_v4l2_device;
+	}
+
+	list_for_each_entry(subdev_entity, &isc->subdev_entities, list) {
+		v4l2_async_notifier_init(&subdev_entity->notifier);
+
+		ret = v4l2_async_notifier_add_subdev(&subdev_entity->notifier,
+						     subdev_entity->asd);
+		if (ret) {
+			fwnode_handle_put(subdev_entity->asd->match.fwnode);
+			kfree(subdev_entity->asd);
+			goto cleanup_subdev;
+		}
+
+		subdev_entity->notifier.ops = &isc_async_ops;
+
+		ret = v4l2_async_notifier_register(&isc->v4l2_dev,
+						   &subdev_entity->notifier);
+		if (ret) {
+			dev_err(dev, "fail to register async notifier\n");
+			goto cleanup_subdev;
+		}
+
+		if (video_is_registered(&isc->video_dev))
+			break;
+	}
+
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+	pm_request_idle(dev);
+
+	return 0;
+
+cleanup_subdev:
+	isc_subdev_cleanup(isc);
+
+unregister_v4l2_device:
+	v4l2_device_unregister(&isc->v4l2_dev);
+
+unprepare_clk:
+	clk_disable_unprepare(isc->ispck);
+unprepare_hclk:
+	clk_disable_unprepare(isc->hclock);
+
+	isc_clk_cleanup(isc);
+
+	return ret;
+}
+
+static int atmel_isc_remove(struct platform_device *pdev)
+{
+	struct isc_device *isc = platform_get_drvdata(pdev);
+
+	pm_runtime_disable(&pdev->dev);
+	clk_disable_unprepare(isc->ispck);
+	clk_disable_unprepare(isc->hclock);
+
+	isc_subdev_cleanup(isc);
+
+	v4l2_device_unregister(&isc->v4l2_dev);
+
+	isc_clk_cleanup(isc);
+
+	return 0;
+}
+
+static int __maybe_unused isc_runtime_suspend(struct device *dev)
+{
+	struct isc_device *isc = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(isc->ispck);
+	clk_disable_unprepare(isc->hclock);
+
+	return 0;
+}
+
+static int __maybe_unused isc_runtime_resume(struct device *dev)
+{
+	struct isc_device *isc = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(isc->hclock);
+	if (ret)
+		return ret;
+
+	return clk_prepare_enable(isc->ispck);
+}
+
+static const struct dev_pm_ops atmel_isc_dev_pm_ops = {
+	SET_RUNTIME_PM_OPS(isc_runtime_suspend, isc_runtime_resume, NULL)
+};
+
+static const struct of_device_id atmel_isc_of_match[] = {
+	{ .compatible = "atmel,sama5d2-isc" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, atmel_isc_of_match);
+
+static struct platform_driver atmel_isc_driver = {
+	.probe	= atmel_isc_probe,
+	.remove	= atmel_isc_remove,
+	.driver	= {
+		.name		= ATMEL_ISC_NAME,
+		.pm		= &atmel_isc_dev_pm_ops,
+		.of_match_table = of_match_ptr(atmel_isc_of_match),
+	},
+};
+
+module_platform_driver(atmel_isc_driver);
+
+MODULE_AUTHOR("Songjun Wu");
+MODULE_DESCRIPTION("The V4L2 driver for Atmel-ISC");
+MODULE_LICENSE("GPL v2");
+MODULE_SUPPORTED_DEVICE("video");