diff options
Diffstat (limited to 'drivers/clk/clk-twl6040.c')
| -rw-r--r-- | drivers/clk/clk-twl6040.c | 76 |
1 files changed, 55 insertions, 21 deletions
diff --git a/drivers/clk/clk-twl6040.c b/drivers/clk/clk-twl6040.c index 7b222a5db931..b8d1cfe5b0e1 100644 --- a/drivers/clk/clk-twl6040.c +++ b/drivers/clk/clk-twl6040.c @@ -1,23 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * TWL6040 clock module driver for OMAP4 McPDM functional clock * * Copyright (C) 2012 Texas Instruments Inc. * Peter Ujfalusi <peter.ujfalusi@ti.com> -* -* This program is free software; you can redistribute it and/or -* modify it under the terms of the GNU General Public License -* version 2 as published by the Free Software Foundation. -* -* This program is distributed in the hope that it will be useful, but -* WITHOUT ANY WARRANTY; without even the implied warranty of -* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU -* General Public License for more details. -* -* You should have received a copy of the GNU General Public License -* along with this program; if not, write to the Free Software -* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA -* 02110-1301 USA -* */ #include <linux/module.h> @@ -41,6 +27,43 @@ static int twl6040_pdmclk_is_prepared(struct clk_hw *hw) return pdmclk->enabled; } +static int twl6040_pdmclk_reset_one_clock(struct twl6040_pdmclk *pdmclk, + unsigned int reg) +{ + const u8 reset_mask = TWL6040_HPLLRST; /* Same for HPPLL and LPPLL */ + int ret; + + ret = twl6040_set_bits(pdmclk->twl6040, reg, reset_mask); + if (ret < 0) + return ret; + + ret = twl6040_clear_bits(pdmclk->twl6040, reg, reset_mask); + if (ret < 0) + return ret; + + return 0; +} + +/* + * TWL6040A2 Phoenix Audio IC erratum #6: "PDM Clock Generation Issue At + * Cold Temperature". This affects cold boot and deeper idle states it + * seems. The workaround consists of resetting HPPLL and LPPLL. + */ +static int twl6040_pdmclk_quirk_reset_clocks(struct twl6040_pdmclk *pdmclk) +{ + int ret; + + ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_HPPLLCTL); + if (ret) + return ret; + + ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_LPPLLCTL); + if (ret) + return ret; + + return 0; +} + static int twl6040_pdmclk_prepare(struct clk_hw *hw) { struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk, @@ -48,8 +71,20 @@ static int twl6040_pdmclk_prepare(struct clk_hw *hw) int ret; ret = twl6040_power(pdmclk->twl6040, 1); - if (!ret) - pdmclk->enabled = 1; + if (ret) + return ret; + + ret = twl6040_pdmclk_quirk_reset_clocks(pdmclk); + if (ret) + goto out_err; + + pdmclk->enabled = 1; + + return 0; + +out_err: + dev_err(pdmclk->dev, "%s: error %i\n", __func__, ret); + twl6040_power(pdmclk->twl6040, 0); return ret; } @@ -82,7 +117,7 @@ static const struct clk_ops twl6040_pdmclk_ops = { .recalc_rate = twl6040_pdmclk_recalc_rate, }; -static struct clk_init_data twl6040_pdmclk_init = { +static const struct clk_init_data twl6040_pdmclk_init = { .name = "pdmclk", .ops = &twl6040_pdmclk_ops, .flags = CLK_GET_RATE_NOCACHE, @@ -108,9 +143,8 @@ static int twl6040_pdmclk_probe(struct platform_device *pdev) platform_set_drvdata(pdev, clkdata); - return of_clk_add_hw_provider(pdev->dev.parent->of_node, - of_clk_hw_simple_get, - &clkdata->pdmclk_hw); + return devm_of_clk_add_hw_provider(&pdev->dev, of_clk_hw_simple_get, + &clkdata->pdmclk_hw); } static struct platform_driver twl6040_pdmclk_driver = { |