1/*
  2 * Copyright (c) 2012-2015, The Linux Foundation. All rights reserved.
  3 *
  4 * This program is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License version 2 and
  6 * only version 2 as published by the Free Software Foundation.
  7 *
  8 * This program is distributed in the hope that it will be useful,
  9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 11 * GNU General Public License for more details.
 12 */
 13
 14#include "dsi_pll.h"
 15
 16static int dsi_pll_enable(struct msm_dsi_pll *pll)
 17{
 18	int i, ret = 0;
 19
 20	/*
 21	 * Certain PLLs do not allow VCO rate update when it is on.
 22	 * Keep track of their status to turn on/off after set rate success.
 23	 */
 24	if (unlikely(pll->pll_on))
 25		return 0;
 26
 27	/* Try all enable sequences until one succeeds */
 28	for (i = 0; i < pll->en_seq_cnt; i++) {
 29		ret = pll->enable_seqs[i](pll);
 30		DBG("DSI PLL %s after sequence #%d",
 31			ret ? "unlocked" : "locked", i + 1);
 32		if (!ret)
 33			break;
 34	}
 35
 36	if (ret) {
 37		DRM_ERROR("DSI PLL failed to lock\n");
 38		return ret;
 39	}
 40
 41	pll->pll_on = true;
 42
 43	return 0;
 44}
 45
 46static void dsi_pll_disable(struct msm_dsi_pll *pll)
 47{
 48	if (unlikely(!pll->pll_on))
 49		return;
 50
 51	pll->disable_seq(pll);
 52
 53	pll->pll_on = false;
 54}
 55
 56/*
 57 * DSI PLL Helper functions
 58 */
 59long msm_dsi_pll_helper_clk_round_rate(struct clk_hw *hw,
 60		unsigned long rate, unsigned long *parent_rate)
 61{
 62	struct msm_dsi_pll *pll = hw_clk_to_pll(hw);
 63
 64	if      (rate < pll->min_rate)
 65		return  pll->min_rate;
 66	else if (rate > pll->max_rate)
 67		return  pll->max_rate;
 68	else
 69		return rate;
 70}
 71
 72int msm_dsi_pll_helper_clk_prepare(struct clk_hw *hw)
 73{
 74	struct msm_dsi_pll *pll = hw_clk_to_pll(hw);
 75
 76	return dsi_pll_enable(pll);
 77}
 78
 79void msm_dsi_pll_helper_clk_unprepare(struct clk_hw *hw)
 80{
 81	struct msm_dsi_pll *pll = hw_clk_to_pll(hw);
 82
 83	dsi_pll_disable(pll);
 84}
 85
 86void msm_dsi_pll_helper_unregister_clks(struct platform_device *pdev,
 87					struct clk **clks, u32 num_clks)
 88{
 89	of_clk_del_provider(pdev->dev.of_node);
 90
 91	if (!num_clks || !clks)
 92		return;
 93
 94	do {
 95		clk_unregister(clks[--num_clks]);
 96		clks[num_clks] = NULL;
 97	} while (num_clks);
 98}
 99
100/*
101 * DSI PLL API
102 */
103int msm_dsi_pll_get_clk_provider(struct msm_dsi_pll *pll,
104	struct clk **byte_clk_provider, struct clk **pixel_clk_provider)
105{
106	if (pll->get_provider)
107		return pll->get_provider(pll,
108					byte_clk_provider,
109					pixel_clk_provider);
110
111	return -EINVAL;
112}
113
114void msm_dsi_pll_destroy(struct msm_dsi_pll *pll)
115{
116	if (pll->destroy)
117		pll->destroy(pll);
118}
119
120void msm_dsi_pll_save_state(struct msm_dsi_pll *pll)
121{
122	if (pll->save_state) {
123		pll->save_state(pll);
124		pll->state_saved = true;
125	}
126}
127
128int msm_dsi_pll_restore_state(struct msm_dsi_pll *pll)
129{
130	int ret;
131
132	if (pll->restore_state && pll->state_saved) {
133		ret = pll->restore_state(pll);
134		if (ret)
135			return ret;
136
137		pll->state_saved = false;
138	}
139
140	return 0;
141}
142
143struct msm_dsi_pll *msm_dsi_pll_init(struct platform_device *pdev,
144			enum msm_dsi_phy_type type, int id)
145{
146	struct device *dev = &pdev->dev;
147	struct msm_dsi_pll *pll;
148
149	switch (type) {
150	case MSM_DSI_PHY_28NM_HPM:
151	case MSM_DSI_PHY_28NM_LP:
152		pll = msm_dsi_pll_28nm_init(pdev, type, id);
153		break;
154	case MSM_DSI_PHY_28NM_8960:
155		pll = msm_dsi_pll_28nm_8960_init(pdev, id);
156		break;
157	default:
158		pll = ERR_PTR(-ENXIO);
159		break;
160	}
161
162	if (IS_ERR(pll)) {
163		dev_err(dev, "%s: failed to init DSI PLL\n", __func__);
164		return NULL;
165	}
166
167	pll->type = type;
168
169	DBG("DSI:%d PLL registered", id);
170
171	return pll;
172}
173