Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934383AbbKSOSE (ORCPT ); Thu, 19 Nov 2015 09:18:04 -0500 Received: from mail-wm0-f46.google.com ([74.125.82.46]:33185 "EHLO mail-wm0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934205AbbKSOSB (ORCPT ); Thu, 19 Nov 2015 09:18:01 -0500 MIME-Version: 1.0 In-Reply-To: <1447940410-9728-1-git-send-email-jacob@teenage.engineering> References: <1447940410-9728-1-git-send-email-jacob@teenage.engineering> Date: Thu, 19 Nov 2015 15:18:00 +0100 Message-ID: Subject: Re: [PATCH] clk: si5351: Add setup steps From: Belisko Marek To: Jacob Siverskog Cc: Michael Turquette , Stephen Boyd , Sebastian Hesselbarth , LKML , linux-clk@vger.kernel.org, Jens Rudberg Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3284 Lines: 87 Hi Jacob, On Thu, Nov 19, 2015 at 2:40 PM, Jacob Siverskog wrote: > This is according to figure 12 ("I2C Programming Procedure") in > "Si5351A/B/C Data Sheet" > (https://www.silabs.com/Support%20Documents/TechnicalDocs/Si5351-B.pdf). > > Without the PLL soft reset, we were unable to get three outputs > working at the same time. > > According to Silicon Labs support, performing PLL soft reset will only > be noticable if the PLL parameters have been changed. > > Signed-off-by: Jacob Siverskog > Signed-off-by: Jens Rudberg > --- > drivers/clk/clk-si5351.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/clk/clk-si5351.c b/drivers/clk/clk-si5351.c > index e346b22..110de35 100644 > --- a/drivers/clk/clk-si5351.c > +++ b/drivers/clk/clk-si5351.c > @@ -1091,6 +1091,11 @@ static int si5351_clkout_set_rate(struct clk_hw *hw, unsigned long rate, > si5351_set_bits(hwdata->drvdata, SI5351_CLK0_CTRL + hwdata->num, > SI5351_CLK_POWERDOWN, 0); > > + /* do a pll soft reset on both plls, needed in some cases to get all > + * outputs running */ ^^^^ wrong format of multi line comment, please look at Documentation/CodingStyle > + si5351_reg_write(hwdata->drvdata, SI5351_PLL_RESET, > + SI5351_PLL_RESET_A | SI5351_PLL_RESET_B); ^^^^ according datasheet PLL_RESET_A/B are self clearing bits valid for Si5351A/C only so probably we need to add some code for B model > + > dev_dbg(&hwdata->drvdata->client->dev, > "%s - %s: rdiv = %u, parent_rate = %lu, rate = %lu\n", > __func__, clk_hw_get_name(hw), (1 << rdiv), > @@ -1359,6 +1364,14 @@ static int si5351_i2c_probe(struct i2c_client *client, > return PTR_ERR(drvdata->regmap); > } > > + /* Disable outputs */ > + si5351_reg_write(drvdata, SI5351_OUTPUT_ENABLE_CTRL, 0xff); > + > + /* Power down all output drivers */ > + for (n = 0; n < 8; n++) { > + si5351_reg_write(drvdata, SI5351_CLK0_CTRL + n, 0x80); > + } ^^^ single line after for statement doesn't need curly braces (if you run ./scripts/check_patch it will complain) > + > /* Disable interrupts */ > si5351_reg_write(drvdata, SI5351_INTERRUPT_MASK, 0xf0); > /* Ensure pll select is on XTAL for Si5351A/B */ > -- > 2.6.3 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ BR, marek -- as simple and primitive as possible ------------------------------------------------- Marek Belisko - OPEN-NANDRA Freelance Developer Ruska Nova Ves 219 | Presov, 08005 Slovak Republic Tel: +421 915 052 184 skype: marekwhite twitter: #opennandra web: http://open-nandra.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/