Hi,
>From: Naveen Kaje <nkaje@xxxxxxxxxxxxxx>
>
>Add support to get the device parameters from ACPI. Assume
>that the clocks are managed by firmware.
>
>Signed-off-by: Naveen Kaje <nkaje@xxxxxxxxxxxxxx>
>Signed-off-by: Austin Christ <austinwc@xxxxxxxxxxxxxx>
>---
> drivers/i2c/busses/i2c-qup.c | 60 ++++++++++++++++++++++++++++++++------------
> 1 file changed, 44 insertions(+), 16 deletions(-)
>
>Changes:
>- v3:
> - clean up unused variable
>- v2:
> - clean up redundant checks and variables
>
>diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c
>index dddd4da..ea6ca5f 100644
>--- a/drivers/i2c/busses/i2c-qup.c
>+++ b/drivers/i2c/busses/i2c-qup.c
>@@ -29,6 +29,7 @@
> #include <linux/platform_device.h>
> #include <linux/pm_runtime.h>
> #include <linux/scatterlist.h>
>+#include <linux/acpi.h>
>
> /* QUP Registers */
> #define QUP_CONFIG 0x000
>@@ -132,6 +133,10 @@
> /* Max timeout in ms for 32k bytes */
> #define TOUT_MAX 300
>
>+/* Default values. Use these if FW query fails */
>+#define DEFAULT_CLK_FREQ 100000
>+#define DEFAULT_SRC_CLK 20000000
>+
> struct qup_i2c_block {
> int count;
> int pos;
>@@ -1354,14 +1359,13 @@ static void qup_i2c_disable_clocks(struct qup_i2c_dev *qup)
> static int qup_i2c_probe(struct platform_device *pdev)
> {
> static const int blk_sizes[] = {4, 16, 32};
>- struct device_node *node = pdev->dev.of_node;
> struct qup_i2c_dev *qup;
> unsigned long one_bit_t;
> struct resource *res;
> u32 io_mode, hw_ver, size;
> int ret, fs_div, hs_div;
>- int src_clk_freq;
>- u32 clk_freq = 100000;
>+ u32 src_clk_freq = 0;
>+ u32 clk_freq = 0;
> int blocks;
>
> qup = devm_kzalloc(&pdev->dev, sizeof(*qup), GFP_KERNEL);
>@@ -1372,7 +1376,12 @@ static int qup_i2c_probe(struct platform_device *pdev)
> init_completion(&qup->xfer);
> platform_set_drvdata(pdev, qup);
>
>- of_property_read_u32(node, "clock-frequency", &clk_freq);
>+ ret = device_property_read_u32(qup->dev, "clock-frequency", &clk_freq);
>+ if (ret) {
>+ dev_warn(qup->dev, "using default clock-frequency %d",
>+ DEFAULT_CLK_FREQ);
>+ clk_freq = DEFAULT_CLK_FREQ;
>+ }
>
> if (of_device_is_compatible(pdev->dev.of_node, "qcom,i2c-qup-v1.1.1")) {
> qup->adap.algo = &qup_i2c_algo;
>@@ -1454,20 +1463,31 @@ nodma:
> return qup->irq;
> }
>
>- qup->clk = devm_clk_get(qup->dev, "core");
>- if (IS_ERR(qup->clk)) {
>- dev_err(qup->dev, "Could not get core clock\n");
>- return PTR_ERR(qup->clk);
>- }
>+ if (ACPI_HANDLE(qup->dev)) {
>+ ret = device_property_read_u32(qup->dev,
>+ "src-clock-hz", &src_clk_freq);
>+ if (ret) {
>+ dev_warn(qup->dev, "using default src-clock-hz %d",
>+ DEFAULT_SRC_CLK);
>+ src_clk_freq = DEFAULT_SRC_CLK;
>+ }
>+ ACPI_COMPANION_SET(&qup->adap.dev, ACPI_COMPANION(qup->dev));
>+ } else {
>+ qup->clk = devm_clk_get(qup->dev, "core");
>+ if (IS_ERR(qup->clk)) {
>+ dev_err(qup->dev, "Could not get core clock\n");
>+ return PTR_ERR(qup->clk);
>+ }
>
>- qup->pclk = devm_clk_get(qup->dev, "iface");
>- if (IS_ERR(qup->pclk)) {
>- dev_err(qup->dev, "Could not get iface clock\n");
>- return PTR_ERR(qup->pclk);
>+ qup->pclk = devm_clk_get(qup->dev, "iface");
>+ if (IS_ERR(qup->pclk)) {
>+ dev_err(qup->dev, "Could not get iface clock\n");
>+ return PTR_ERR(qup->pclk);
>+ }
>+ qup_i2c_enable_clocks(qup);
>+ src_clk_freq = clk_get_rate(qup->clk);
> }
>
>- qup_i2c_enable_clocks(qup);
>-
> /*
> * Bootloaders might leave a pending interrupt on certain QUP's,
> * so we reset the core before registering for interrupts.
>@@ -1514,7 +1534,6 @@ nodma:
> size = QUP_INPUT_FIFO_SIZE(io_mode);
> qup->in_fifo_sz = qup->in_blk_sz * (2 << size);
>
>- src_clk_freq = clk_get_rate(qup->clk);
> fs_div = ((src_clk_freq / clk_freq) / 2) - 3;
> hs_div = 3;
> qup->clk_ctl = (hs_div << 8) | (fs_div & 0xff);
>@@ -1639,6 +1658,14 @@ static const struct of_device_id qup_i2c_dt_match[] = {
> };
> MODULE_DEVICE_TABLE(of, qup_i2c_dt_match);
>
>+#if IS_ENABLED(CONFIG_ACPI)
>+static const struct acpi_device_id qup_i2c_acpi_match[] = {
>+ { "QCOM8010"},
>+ { },
>+};
>+MODULE_DEVICE_TABLE(acpi, qup_i2c_acpi_ids);
>+#endif
>+
> static struct platform_driver qup_i2c_driver = {
> .probe = qup_i2c_probe,
> .remove = qup_i2c_remove,
>@@ -1646,6 +1673,7 @@ static struct platform_driver qup_i2c_driver = {
> .name = "i2c_qup",
> .pm = &qup_i2c_qup_pm_ops,
> .of_match_table = qup_i2c_dt_match,
>+ .acpi_match_table = ACPI_PTR(qup_i2c_acpi_match),
> },
> };
Reviewed-by: sricharan@xxxxxxxxxxxxxx
Regards,
Sricharan
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