From: Heiner Kallweit <hkallweit1@gmail.com> To: Wolfram Sang <wsa@the-dreams.de>, Jerome Brunet <jbrunet@baylibre.com>, Kevin Hilman <khilman@baylibre.com> Cc: "linux-i2c@vger.kernel.org" <linux-i2c@vger.kernel.org>, linux-amlogic@lists.infradead.org Subject: [PATCH v5 03/10] i2c: meson: set clock divider in probe instead of setting it for each transfer Date: Sat, 25 Mar 2017 14:04:42 +0100 [thread overview] Message-ID: <c247c090-68c9-7aa0-867f-362052ed82d7@gmail.com> (raw) In-Reply-To: <645519b8-93e6-57b1-ae8f-7804c6beb9b1@gmail.com> The bus frequency is fixed to what is set DT, therefore we can set the clock divider in probe already and we don't have to set it for each transfer. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- v2: - no changes v3: - change order of patches v4: - no changes v5: - improved commit message --- drivers/i2c/busses/i2c-meson.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/drivers/i2c/busses/i2c-meson.c b/drivers/i2c/busses/i2c-meson.c index 50059d09..e597764e 100644 --- a/drivers/i2c/busses/i2c-meson.c +++ b/drivers/i2c/busses/i2c-meson.c @@ -73,7 +73,6 @@ enum { * @error: Flag set when an error is received * @lock: To avoid race conditions between irq handler and xfer code * @done: Completion used to wait for transfer termination - * @frequency: Operating frequency of I2C bus clock * @tokens: Sequence of tokens to be written to the device * @num_tokens: Number of tokens */ @@ -92,7 +91,6 @@ struct meson_i2c { spinlock_t lock; struct completion done; - unsigned int frequency; u32 tokens[2]; int num_tokens; }; @@ -131,17 +129,17 @@ static void meson_i2c_write_tokens(struct meson_i2c *i2c) writel(i2c->tokens[1], i2c->regs + REG_TOK_LIST1); } -static void meson_i2c_set_clk_div(struct meson_i2c *i2c) +static void meson_i2c_set_clk_div(struct meson_i2c *i2c, unsigned int freq) { unsigned long clk_rate = clk_get_rate(i2c->clk); unsigned int div; - div = DIV_ROUND_UP(clk_rate, i2c->frequency * 4); + div = DIV_ROUND_UP(clk_rate, freq * 4); meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_CLKDIV_MASK, div << REG_CTRL_CLKDIV_SHIFT); dev_dbg(i2c->dev, "%s: clk %lu, freq %u, div %u\n", __func__, - clk_rate, i2c->frequency, div); + clk_rate, freq, div); } static void meson_i2c_get_data(struct meson_i2c *i2c, char *buf, int len) @@ -361,7 +359,6 @@ static int meson_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int i, ret = 0, count = 0; clk_enable(i2c->clk); - meson_i2c_set_clk_div(i2c); for (i = 0; i < num; i++) { ret = meson_i2c_xfer_msg(i2c, msgs + i, i == num - 1); @@ -390,15 +387,15 @@ static int meson_i2c_probe(struct platform_device *pdev) struct device_node *np = pdev->dev.of_node; struct meson_i2c *i2c; struct resource *mem; + u32 freq; int irq, ret = 0; i2c = devm_kzalloc(&pdev->dev, sizeof(struct meson_i2c), GFP_KERNEL); if (!i2c) return -ENOMEM; - if (of_property_read_u32(pdev->dev.of_node, "clock-frequency", - &i2c->frequency)) - i2c->frequency = DEFAULT_FREQ; + if (of_property_read_u32(pdev->dev.of_node, "clock-frequency", &freq)) + freq = DEFAULT_FREQ; i2c->dev = &pdev->dev; platform_set_drvdata(pdev, i2c); @@ -456,6 +453,8 @@ static int meson_i2c_probe(struct platform_device *pdev) return ret; } + meson_i2c_set_clk_div(i2c, freq); + return 0; } -- 2.12.0
WARNING: multiple messages have this Message-ID (diff)
From: hkallweit1@gmail.com (Heiner Kallweit) To: linus-amlogic@lists.infradead.org Subject: [PATCH v5 03/10] i2c: meson: set clock divider in probe instead of setting it for each transfer Date: Sat, 25 Mar 2017 14:04:42 +0100 [thread overview] Message-ID: <c247c090-68c9-7aa0-867f-362052ed82d7@gmail.com> (raw) In-Reply-To: <645519b8-93e6-57b1-ae8f-7804c6beb9b1@gmail.com> The bus frequency is fixed to what is set DT, therefore we can set the clock divider in probe already and we don't have to set it for each transfer. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- v2: - no changes v3: - change order of patches v4: - no changes v5: - improved commit message --- drivers/i2c/busses/i2c-meson.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/drivers/i2c/busses/i2c-meson.c b/drivers/i2c/busses/i2c-meson.c index 50059d09..e597764e 100644 --- a/drivers/i2c/busses/i2c-meson.c +++ b/drivers/i2c/busses/i2c-meson.c @@ -73,7 +73,6 @@ enum { * @error: Flag set when an error is received * @lock: To avoid race conditions between irq handler and xfer code * @done: Completion used to wait for transfer termination - * @frequency: Operating frequency of I2C bus clock * @tokens: Sequence of tokens to be written to the device * @num_tokens: Number of tokens */ @@ -92,7 +91,6 @@ struct meson_i2c { spinlock_t lock; struct completion done; - unsigned int frequency; u32 tokens[2]; int num_tokens; }; @@ -131,17 +129,17 @@ static void meson_i2c_write_tokens(struct meson_i2c *i2c) writel(i2c->tokens[1], i2c->regs + REG_TOK_LIST1); } -static void meson_i2c_set_clk_div(struct meson_i2c *i2c) +static void meson_i2c_set_clk_div(struct meson_i2c *i2c, unsigned int freq) { unsigned long clk_rate = clk_get_rate(i2c->clk); unsigned int div; - div = DIV_ROUND_UP(clk_rate, i2c->frequency * 4); + div = DIV_ROUND_UP(clk_rate, freq * 4); meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_CLKDIV_MASK, div << REG_CTRL_CLKDIV_SHIFT); dev_dbg(i2c->dev, "%s: clk %lu, freq %u, div %u\n", __func__, - clk_rate, i2c->frequency, div); + clk_rate, freq, div); } static void meson_i2c_get_data(struct meson_i2c *i2c, char *buf, int len) @@ -361,7 +359,6 @@ static int meson_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int i, ret = 0, count = 0; clk_enable(i2c->clk); - meson_i2c_set_clk_div(i2c); for (i = 0; i < num; i++) { ret = meson_i2c_xfer_msg(i2c, msgs + i, i == num - 1); @@ -390,15 +387,15 @@ static int meson_i2c_probe(struct platform_device *pdev) struct device_node *np = pdev->dev.of_node; struct meson_i2c *i2c; struct resource *mem; + u32 freq; int irq, ret = 0; i2c = devm_kzalloc(&pdev->dev, sizeof(struct meson_i2c), GFP_KERNEL); if (!i2c) return -ENOMEM; - if (of_property_read_u32(pdev->dev.of_node, "clock-frequency", - &i2c->frequency)) - i2c->frequency = DEFAULT_FREQ; + if (of_property_read_u32(pdev->dev.of_node, "clock-frequency", &freq)) + freq = DEFAULT_FREQ; i2c->dev = &pdev->dev; platform_set_drvdata(pdev, i2c); @@ -456,6 +453,8 @@ static int meson_i2c_probe(struct platform_device *pdev) return ret; } + meson_i2c_set_clk_div(i2c, freq); + return 0; } -- 2.12.0
next prev parent reply other threads:[~2017-03-25 13:14 UTC|newest] Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-03-25 12:57 [PATCH v5 00/10] i2c: meson: series with improvements Heiner Kallweit 2017-03-25 12:57 ` Heiner Kallweit 2017-03-25 12:58 ` [PATCH v5 01/10] i2c: meson: use min instead of min_t where min_t isn't needed Heiner Kallweit 2017-03-25 12:58 ` Heiner Kallweit 2017-03-25 13:01 ` [PATCH v5 02/10] i2c: meson: remove member irq from struct meson_i2c Heiner Kallweit 2017-03-25 13:01 ` Heiner Kallweit 2017-03-25 13:04 ` Heiner Kallweit [this message] 2017-03-25 13:04 ` [PATCH v5 03/10] i2c: meson: set clock divider in probe instead of setting it for each transfer Heiner Kallweit 2017-03-25 13:06 ` [PATCH v5 04/10] i2c: meson: use i2c core for DT clock-frequency parsing Heiner Kallweit 2017-03-25 13:06 ` Heiner Kallweit 2017-03-25 13:07 ` [PATCH v5 05/10] i2c: meson: use full 12 bits for clock divider Heiner Kallweit 2017-03-25 13:07 ` Heiner Kallweit 2017-03-25 13:09 ` [PATCH v5 06/10] i2c: meson: remove variable count from meson_i2c_xfer Heiner Kallweit 2017-03-25 13:09 ` Heiner Kallweit 2017-03-25 13:10 ` [PATCH v5 07/10] i2c: meson: improve interrupt handler and detect spurious interrupts Heiner Kallweit 2017-03-25 13:10 ` Heiner Kallweit 2017-03-25 13:11 ` [PATCH v5 08/10] i2c: meson: don't create separate token chain just for the stop command Heiner Kallweit 2017-03-25 13:11 ` Heiner Kallweit 2017-03-25 13:12 ` [PATCH v5 09/10] i2c: meson: remove meson_i2c_write_tokens Heiner Kallweit 2017-03-25 13:12 ` Heiner Kallweit 2017-03-25 13:14 ` [PATCH v5 10/10] i2c: meson: improve and simplify interrupt handler Heiner Kallweit 2017-03-25 13:14 ` Heiner Kallweit 2017-03-30 15:56 ` [PATCH v5 00/10] i2c: meson: series with improvements Wolfram Sang 2017-03-30 15:56 ` Wolfram Sang
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