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brintos / linux-shallow public Read only

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1/*2 * Copyright 2015 Red Hat Inc.3 *4 * Permission is hereby granted, free of charge, to any person obtaining a5 * copy of this software and associated documentation files (the "Software"),6 * to deal in the Software without restriction, including without limitation7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,8 * and/or sell copies of the Software, and to permit persons to whom the9 * Software is furnished to do so, subject to the following conditions:10 *11 * The above copyright notice and this permission notice shall be included in12 * all copies or substantial busions of the Software.13 *14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR20 * OTHER DEALINGS IN THE SOFTWARE.21 *22 * Authors: Ben Skeggs <bskeggs@redhat.com>23 */24#define g94_i2c_aux(p) container_of((p), struct g94_i2c_aux, base)25#include "aux.h"26 27struct g94_i2c_aux {28	struct nvkm_i2c_aux base;29	int ch;30};31 32static void33g94_i2c_aux_fini(struct g94_i2c_aux *aux)34{35	struct nvkm_device *device = aux->base.pad->i2c->subdev.device;36	nvkm_mask(device, 0x00e4e4 + (aux->ch * 0x50), 0x00310000, 0x00000000);37}38 39static int40g94_i2c_aux_init(struct g94_i2c_aux *aux)41{42	struct nvkm_device *device = aux->base.pad->i2c->subdev.device;43	const u32 unksel = 1; /* nfi which to use, or if it matters.. */44	const u32 ureq = unksel ? 0x00100000 : 0x00200000;45	const u32 urep = unksel ? 0x01000000 : 0x02000000;46	u32 ctrl, timeout;47 48	/* wait up to 1ms for any previous transaction to be done... */49	timeout = 1000;50	do {51		ctrl = nvkm_rd32(device, 0x00e4e4 + (aux->ch * 0x50));52		udelay(1);53		if (!timeout--) {54			AUX_ERR(&aux->base, "begin idle timeout %08x", ctrl);55			return -EBUSY;56		}57	} while (ctrl & 0x03010000);58 59	/* set some magic, and wait up to 1ms for it to appear */60	nvkm_mask(device, 0x00e4e4 + (aux->ch * 0x50), 0x00300000, ureq);61	timeout = 1000;62	do {63		ctrl = nvkm_rd32(device, 0x00e4e4 + (aux->ch * 0x50));64		udelay(1);65		if (!timeout--) {66			AUX_ERR(&aux->base, "magic wait %08x", ctrl);67			g94_i2c_aux_fini(aux);68			return -EBUSY;69		}70	} while ((ctrl & 0x03000000) != urep);71 72	return 0;73}74 75int76g94_i2c_aux_xfer(struct nvkm_i2c_aux *obj, bool retry,77		 u8 type, u32 addr, u8 *data, u8 *size)78{79	struct g94_i2c_aux *aux = g94_i2c_aux(obj);80	struct nvkm_i2c *i2c = aux->base.pad->i2c;81	struct nvkm_device *device = i2c->subdev.device;82	const u32 base = aux->ch * 0x50;83	u32 ctrl, stat, timeout, retries = 0;84	u32 xbuf[4] = {};85	int ret, i;86 87	AUX_TRACE(&aux->base, "%d: %08x %d", type, addr, *size);88 89	ret = g94_i2c_aux_init(aux);90	if (ret < 0)91		goto out;92 93	stat = nvkm_rd32(device, 0x00e4e8 + base);94	if (!(stat & 0x10000000)) {95		AUX_TRACE(&aux->base, "sink not detected");96		ret = -ENXIO;97		goto out;98	}99 100	nvkm_i2c_aux_autodpcd(i2c, aux->ch, false);101 102	if (!(type & 1)) {103		memcpy(xbuf, data, *size);104		for (i = 0; i < 16; i += 4) {105			AUX_TRACE(&aux->base, "wr %08x", xbuf[i / 4]);106			nvkm_wr32(device, 0x00e4c0 + base + i, xbuf[i / 4]);107		}108	}109 110	ctrl  = nvkm_rd32(device, 0x00e4e4 + base);111	ctrl &= ~0x0001f1ff;112	ctrl |= type << 12;113	ctrl |= (*size ? (*size - 1) : 0x00000100);114	nvkm_wr32(device, 0x00e4e0 + base, addr);115 116	/* (maybe) retry transaction a number of times on failure... */117	do {118		/* reset, and delay a while if this is a retry */119		nvkm_wr32(device, 0x00e4e4 + base, 0x80000000 | ctrl);120		nvkm_wr32(device, 0x00e4e4 + base, 0x00000000 | ctrl);121		if (retries)122			udelay(400);123 124		/* transaction request, wait up to 2ms for it to complete */125		nvkm_wr32(device, 0x00e4e4 + base, 0x00010000 | ctrl);126 127		timeout = 2000;128		do {129			ctrl = nvkm_rd32(device, 0x00e4e4 + base);130			udelay(1);131			if (!timeout--) {132				AUX_ERR(&aux->base, "timeout %08x", ctrl);133				ret = -EIO;134				goto out_err;135			}136		} while (ctrl & 0x00010000);137		ret = 0;138 139		/* read status, and check if transaction completed ok */140		stat = nvkm_mask(device, 0x00e4e8 + base, 0, 0);141		if ((stat & 0x000f0000) == 0x00080000 ||142		    (stat & 0x000f0000) == 0x00020000)143			ret = 1;144		if ((stat & 0x00000100))145			ret = -ETIMEDOUT;146		if ((stat & 0x00000e00))147			ret = -EIO;148 149		AUX_TRACE(&aux->base, "%02d %08x %08x", retries, ctrl, stat);150	} while (ret && retry && retries++ < 32);151 152	if (type & 1) {153		for (i = 0; i < 16; i += 4) {154			xbuf[i / 4] = nvkm_rd32(device, 0x00e4d0 + base + i);155			AUX_TRACE(&aux->base, "rd %08x", xbuf[i / 4]);156		}157		memcpy(data, xbuf, *size);158		*size = stat & 0x0000001f;159	}160out_err:161	nvkm_i2c_aux_autodpcd(i2c, aux->ch, true);162out:163	g94_i2c_aux_fini(aux);164	return ret < 0 ? ret : (stat & 0x000f0000) >> 16;165}166 167int168g94_i2c_aux_new_(const struct nvkm_i2c_aux_func *func,169		 struct nvkm_i2c_pad *pad, int index, u8 drive,170		 struct nvkm_i2c_aux **paux)171{172	struct g94_i2c_aux *aux;173 174	if (!(aux = kzalloc(sizeof(*aux), GFP_KERNEL)))175		return -ENOMEM;176	*paux = &aux->base;177 178	nvkm_i2c_aux_ctor(func, pad, index, &aux->base);179	aux->ch = drive;180	aux->base.intr = 1 << aux->ch;181	return 0;182}183 184static const struct nvkm_i2c_aux_func185g94_i2c_aux = {186	.xfer = g94_i2c_aux_xfer,187};188 189int190g94_i2c_aux_new(struct nvkm_i2c_pad *pad, int index, u8 drive,191		struct nvkm_i2c_aux **paux)192{193	return g94_i2c_aux_new_(&g94_i2c_aux, pad, index, drive, paux);194}195