Commit 9efc583e authored by Ben Skeggs's avatar Ben Skeggs
Browse files

drm/nouveau/i2c: introduce locking at a per-port level 



There's also provisions to allow a pad to be locked with a specific
routing, for an indefinite period of time.  This will be used in
future patches.

The G94+ pad driver will now also power-down pads when not required.

Signed-off-by: default avatarBen Skeggs <bskeggs@redhat.com>
parent d2ae2eb4

drivers/gpu/drm/nouveau/Makefile

+3 −0
Original line number Diff line number Diff line
@@ -132,6 +132,9 @@ nouveau-y += core/subdev/i2c/base.o 
nouveau-y += core/subdev/i2c/anx9805.o

nouveau-y += core/subdev/i2c/aux.o

nouveau-y += core/subdev/i2c/bit.o

nouveau-y += core/subdev/i2c/pad.o

nouveau-y += core/subdev/i2c/padnv04.o

nouveau-y += core/subdev/i2c/padnv94.o

nouveau-y += core/subdev/i2c/nv04.o

nouveau-y += core/subdev/i2c/nv4e.o

nouveau-y += core/subdev/i2c/nv50.o

drivers/gpu/drm/nouveau/core/include/subdev/i2c.h

+5 −3
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ enum nvkm_i2c_event { 
struct nouveau_i2c_port {

	struct nouveau_object base;

	struct i2c_adapter adapter;

	struct mutex mutex;



	struct list_head head;

	u8  index;
@@ -37,9 +38,6 @@ struct nouveau_i2c_port { 
};



struct nouveau_i2c_func {

	void (*acquire)(struct nouveau_i2c_port *);

	void (*release)(struct nouveau_i2c_port *);



	void (*drive_scl)(struct nouveau_i2c_port *, int);

	void (*drive_sda)(struct nouveau_i2c_port *, int);

	int  (*sense_scl)(struct nouveau_i2c_port *);
@@ -62,12 +60,16 @@ struct nouveau_i2c { 


	struct nouveau_i2c_port *(*find)(struct nouveau_i2c *, u8 index);

	struct nouveau_i2c_port *(*find_type)(struct nouveau_i2c *, u16 type);

	int  (*acquire_pad)(struct nouveau_i2c_port *, unsigned long timeout);

	void (*release_pad)(struct nouveau_i2c_port *);

	int  (*acquire)(struct nouveau_i2c_port *, unsigned long timeout);

	void (*release)(struct nouveau_i2c_port *);

	int (*identify)(struct nouveau_i2c *, int index,

			const char *what, struct nouveau_i2c_board_info *,

			bool (*match)(struct nouveau_i2c_port *,

				      struct i2c_board_info *, void *), void *);



	wait_queue_head_t wait;

	struct list_head ports;

};

drivers/gpu/drm/nouveau/core/subdev/i2c/base.c

+94 −8
Original line number Diff line number Diff line
@@ -31,6 +31,7 @@ 
#include <subdev/vga.h>



#include "priv.h"

#include "pad.h"



/******************************************************************************

 * interface to linux i2c bit-banging algorithm
@@ -90,6 +91,15 @@ nouveau_i2c_getsda(void *data) 
 * base i2c "port" class implementation

 *****************************************************************************/



int

_nouveau_i2c_port_fini(struct nouveau_object *object, bool suspend)

{

	struct nouveau_i2c_port *port = (void *)object;

	struct nvkm_i2c_pad *pad = nvkm_i2c_pad(port);

	nv_ofuncs(pad)->fini(nv_object(pad), suspend);

	return nouveau_object_fini(&port->base, suspend);

}



void

_nouveau_i2c_port_dtor(struct nouveau_object *object)

{
@@ -106,7 +116,7 @@ nouveau_i2c_port_create_(struct nouveau_object *parent, 
			 const struct nouveau_i2c_func *func,

			 int size, void **pobject)

{

	struct nouveau_device *device = nv_device(parent);

	struct nouveau_device *device = nv_device(engine);

	struct nouveau_i2c *i2c = (void *)engine;

	struct nouveau_i2c_port *port;

	int ret;
@@ -123,6 +133,7 @@ nouveau_i2c_port_create_(struct nouveau_object *parent, 
	port->index = index;

	port->aux = -1;

	port->func = func;

	mutex_init(&port->mutex);



	if ( algo == &nouveau_i2c_bit_algo &&

	    !nouveau_boolopt(device->cfgopt, "NvI2C", CSTMSEL)) {
@@ -201,19 +212,73 @@ nouveau_i2c_find_type(struct nouveau_i2c *i2c, u16 type) 
	return NULL;

}



static void

nouveau_i2c_release_pad(struct nouveau_i2c_port *port)

{

	struct nvkm_i2c_pad *pad = nvkm_i2c_pad(port);

	struct nouveau_i2c *i2c = nouveau_i2c(port);



	if (atomic_dec_and_test(&nv_object(pad)->usecount)) {

		nv_ofuncs(pad)->fini(nv_object(pad), false);

		wake_up_all(&i2c->wait);

	}

}



static int

nouveau_i2c_try_acquire_pad(struct nouveau_i2c_port *port)

{

	struct nvkm_i2c_pad *pad = nvkm_i2c_pad(port);



	if (atomic_add_return(1, &nv_object(pad)->usecount) != 1) {

		struct nouveau_object *owner = (void *)pad->port;

		do {

			if (owner == (void *)port)

				return 0;

			owner = owner->parent;

		} while(owner);

		nouveau_i2c_release_pad(port);

		return -EBUSY;

	}



	pad->next = port;

	nv_ofuncs(pad)->init(nv_object(pad));

	return 0;

}



static int

nouveau_i2c_acquire_pad(struct nouveau_i2c_port *port, unsigned long timeout)

{

	struct nouveau_i2c *i2c = nouveau_i2c(port);



	if (timeout) {

		if (wait_event_timeout(i2c->wait,

				       nouveau_i2c_try_acquire_pad(port) == 0,

				       timeout) == 0)

			return -EBUSY;

	} else {

		wait_event(i2c->wait, nouveau_i2c_try_acquire_pad(port) == 0);

	}



	return 0;

}



static void

nouveau_i2c_release(struct nouveau_i2c_port *port)

__releases(pad->mutex)

{

	if (port->func->release)

		port->func->release(port);

	nouveau_i2c(port)->release_pad(port);

	mutex_unlock(&port->mutex);

}



static int

nouveau_i2c_acquire(struct nouveau_i2c_port *port, unsigned long timeout)

__acquires(pad->mutex)

{

	if (port->func->acquire)

		port->func->acquire(port);

	return 0;

	int ret;

	mutex_lock(&port->mutex);

	if ((ret = nouveau_i2c(port)->acquire_pad(port, timeout)))

		mutex_unlock(&port->mutex);

	return ret;

}



static int
@@ -391,7 +456,7 @@ nouveau_i2c_create_(struct nouveau_object *parent, 
	struct nouveau_i2c *i2c;

	struct nouveau_object *object;

	struct dcb_i2c_entry info;

	int ret, i, j, index = -1;

	int ret, i, j, index = -1, pad;

	struct dcb_output outp;

	u8  ver, hdr;

	u32 data;
@@ -405,24 +470,45 @@ nouveau_i2c_create_(struct nouveau_object *parent, 
	nv_subdev(i2c)->intr = nouveau_i2c_intr;

	i2c->find = nouveau_i2c_find;

	i2c->find_type = nouveau_i2c_find_type;

	i2c->acquire_pad = nouveau_i2c_acquire_pad;

	i2c->release_pad = nouveau_i2c_release_pad;

	i2c->acquire = nouveau_i2c_acquire;

	i2c->release = nouveau_i2c_release;

	i2c->identify = nouveau_i2c_identify;

	init_waitqueue_head(&i2c->wait);

	INIT_LIST_HEAD(&i2c->ports);



	while (!dcb_i2c_parse(bios, ++index, &info)) {

		if (info.type == DCB_I2C_UNUSED)

			continue;



		if (info.share != DCB_I2C_UNUSED) {

			if (info.type == DCB_I2C_NVIO_AUX)

				pad = info.drive;

			else

				pad = info.share;

			oclass = impl->pad_s;

		} else {

			pad = 0x100 + info.drive;

			oclass = impl->pad_x;

		}



		ret = nouveau_object_ctor(NULL, *pobject, oclass,

					  NULL, pad, &parent);

		if (ret < 0)

			continue;



		oclass = impl->sclass;

		do {

			ret = -EINVAL;

			if (oclass->handle == info.type) {

				ret = nouveau_object_ctor(*pobject, *pobject,

				ret = nouveau_object_ctor(parent, *pobject,

							  oclass, &info,

							  index, &object);

			}

		} while (ret && (++oclass)->handle);



		nouveau_object_ref(NULL, &parent);

	}



	/* in addition to the busses specified in the i2c table, there

drivers/gpu/drm/nouveau/core/subdev/i2c/nv04.c

+1 −0
Original line number Diff line number Diff line
@@ -126,4 +126,5 @@ nv04_i2c_oclass = &(struct nouveau_i2c_impl) { 
		.fini = _nouveau_i2c_fini,

	},

	.sclass = nv04_i2c_sclass,

	.pad_x = &nv04_i2c_pad_oclass,

}.base;

drivers/gpu/drm/nouveau/core/subdev/i2c/nv4e.c

+1 −0
Original line number Diff line number Diff line
@@ -118,4 +118,5 @@ nv4e_i2c_oclass = &(struct nouveau_i2c_impl) { 
		.fini = _nouveau_i2c_fini,

	},

	.sclass = nv4e_i2c_sclass,

	.pad_x = &nv04_i2c_pad_oclass,

}.base;

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