Messages in this thread Patch in this message | | | From | Marek Behún <> | Subject | [PATCH linux-phy 2/4] device property: Add {fwnode/device}_get_tx_p2p_amplitude() | Date | Wed, 17 Aug 2022 21:31:17 +0200 |
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Add functions fwnode_get_tx_p2p_amplitude() and device_get_tx_p2p_amplitude() that parse the 'tx-p2p-microvolt' and 'tx-p2p-microvolt-names' properties and return peak to peak transmit amplitude in microvolts for given PHY mode.
The functions search for mode name in 'tx-p2p-microvolt-names' property, and return amplitude at the corresponding index in the 'tx-p2p-microvolt' property.
If given mode is not matched in 'tx-p2p-microvolt-names' array, the mode name is generalized (for example "pcie3" -> "pcie" -> "default", or "usb-ss" -> "usb" -> "default").
If the 'tx-p2p-microvolt-names' is not present, the 'tx-p2p-microvolt' property is expected to contain only one value, which is considered default, and will be returned for any mode.
Signed-off-by: Marek Behún <kabel@kernel.org> --- Andy et al. can I get Ack for this if this is okay? --- drivers/base/property.c | 130 +++++++++++++++++++++++++++++++++++++++ include/linux/property.h | 5 ++ 2 files changed, 135 insertions(+)
diff --git a/drivers/base/property.c b/drivers/base/property.c index ed6f449f8e5c..34b763436c30 100644 --- a/drivers/base/property.c +++ b/drivers/base/property.c @@ -921,6 +921,136 @@ int device_get_phy_mode(struct device *dev) } EXPORT_SYMBOL_GPL(device_get_phy_mode); +/** + * fwnode_get_tx_p2p_amplitude - Get peak to peak transmit amplitude for given + * PHY mode + * @fwnode: Pointer to the given node + * @mode: Name of the PHY mode, or "default" / NULL + * @amplitude: Pointer where to store the amplitude + * + * Gets the peak to peak transmit amplitude in microvolts for a given PHY mode + * by parsing the 'tx-p2p-microvolt' and 'tx-p2p-microvolt-names' properties. + * If amplitude is not specified for @mode exactly, tries a more generic mode, + * and if that isn't specified, tries "default". + * + * For example if @mode is "pcie3", we first try searching for value + * corresponding to "pcie3", then to "pcie", and finally to "default". + * + * Return: %0 if the amplitude was read (success), + * %-EINVAL if given arguments are not valid, + * %-ENODATA if the required properties do not have a value, + * %-EPROTO if the property is not an array of strings, + * %-ENXIO if no suitable firmware interface is present, + * %-ENOMEM if out of memory. + */ +int fwnode_get_tx_p2p_amplitude(struct fwnode_handle *fwnode, const char *mode, + u32 *amplitude) +{ + static const char *names_prop = "tx-p2p-microvolt-names", + *vals_prop = "tx-p2p-microvolt"; + const char **names; + int cnt, idx, ret; + u32 *vals; + + cnt = fwnode_property_string_array_count(fwnode, names_prop); + if (!cnt || cnt == -EINVAL) + /* + * If the names property does not exist or is empty, we expect + * the values property to contain only one, default value. + */ + return fwnode_property_read_u32(fwnode, vals_prop, amplitude); + else if (cnt < 0) + return cnt; + + names = kcalloc(cnt, sizeof(*names), GFP_KERNEL); + if (!names) + return -ENOMEM; + + ret = fwnode_property_read_string_array(fwnode, names_prop, names, cnt); + if (ret < 0) { + kfree(names); + return ret; + } + + if (!mode) + mode = "default"; + + do { + static const char *gen_table[] = { + "pcie", "usb", "ufs-hs", "dp", "mipi-dphy", + }; + size_t i; + + idx = match_string(names, cnt, mode); + if (idx >= 0) + break; + + /* If mode was not matched, try more generic mode */ + for (i = 0; i < ARRAY_SIZE(gen_table); ++i) { + if (str_has_proper_prefix(mode, gen_table[i])) { + mode = gen_table[i]; + break; + } + } + + /* Or "default" */ + if (i == ARRAY_SIZE(gen_table)) { + if (strcmp(mode, "default")) + mode = "default"; + else + mode = NULL; + } + } while (mode); + + kfree(names); + + if (idx < 0) + return -ENODATA; + + vals = kcalloc(cnt, sizeof(*vals), GFP_KERNEL); + if (!vals) + return -ENOMEM; + + ret = fwnode_property_read_u32_array(fwnode, vals_prop, vals, cnt); + if (ret) + goto out; + + *amplitude = vals[idx]; +out: + kfree(vals); + return ret; +} +EXPORT_SYMBOL_GPL(fwnode_get_tx_p2p_amplitude); + +/** + * device_get_tx_p2p_amplitude - Get peak to peak transmit amplitude for given + * PHY mode + * @dev: Pointer to the given device + * @mode: Name of the PHY mode, or "default" / NULL + * @amplitude: Pointer where to store the amplitude + * + * Gets the peak to peak transmit amplitude in microvolts for a given PHY mode + * by parsing the 'tx-p2p-microvolt' and 'tx-p2p-microvolt-names' properties. + * If amplitude is not specified for @mode exactly, tries a more generic mode, + * and if that isn't specified, tries "default". + * + * For example if @mode is "pcie3", we first try searching for value + * corresponding to "pcie3", then to "pcie", and finally to "default". + * + * Return: %0 if the amplitude was read (success), + * %-EINVAL if given arguments are not valid, + * %-ENODATA if the required properties do not have a value, + * %-EPROTO if the property is not an array of strings, + * %-ENXIO if no suitable firmware interface is present, + * %-ENOMEM if out of memory. + */ +int device_get_tx_p2p_amplitude(struct device *dev, const char *mode, + u32 *amplitude) +{ + return fwnode_get_tx_p2p_amplitude(dev_fwnode(dev), mode, amplitude); +} +EXPORT_SYMBOL_GPL(device_get_tx_p2p_amplitude); + /** * fwnode_iomap - Maps the memory mapped IO for a given fwnode * @fwnode: Pointer to the firmware node diff --git a/include/linux/property.h b/include/linux/property.h index a5b429d623f6..91b12a79e245 100644 --- a/include/linux/property.h +++ b/include/linux/property.h @@ -392,6 +392,11 @@ const void *device_get_match_data(struct device *dev); int device_get_phy_mode(struct device *dev); int fwnode_get_phy_mode(struct fwnode_handle *fwnode); +int fwnode_get_tx_p2p_amplitude(struct fwnode_handle *fwnode, const char *mode, + u32 *amplitude); +int device_get_tx_p2p_amplitude(struct device *dev, const char *mode, + u32 *amplitude); + void __iomem *fwnode_iomap(struct fwnode_handle *fwnode, int index); struct fwnode_handle *fwnode_graph_get_next_endpoint( -- 2.35.1
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